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Primes 2u-1 with smooth u


This page carries the second link of the smooth-successor route: from the Type II estimate for factorizations of 2u-1 to a count of primes pp with P+(p+1)≤xδP^+(p+1)\le x^\delta, and from it to Hypothesis A+\mathrm A^+. The extraction is OpenAI's, from Section 7 of the weighted-dilation manuscript; running it on primes 2u−12u-1 is Shisheng Li and Zhong Zhuang's proposal; the derivation and checks below are Plasma AI's. The conditional-chain examination of 2026-10-15 has a distinct passing grade, examined on 2026-10-16 UTC, for the frozen balanced extraction conditional on exact P and the stated classical premises. The unrestricted dyadic assertion remains refuted-as-stated.

Besides the signed Type II estimate, which assumes premise (P), the argument uses the following source results. Together with the Section 2 estimates they are premise (E) of the combined sketch. They concern uu or ordinary factor tests; the only occurrence of NuN_u is a size relation in (7.17).

  • Proposition 7.1 (candidate mass) concerns AA, XAX_A and the prime factors of uu only.
  • Lemma 7.3 (proxy discrepancy) concerns the factor tests and their proxies only.
  • Lemma 7.4 (proxy density bounds and the Buchstab identity). Its bound (7.17) is stated for factorizations mn=Numn=N_u; its proof uses NuN_u only through Nu≍xN_u\asymp x, which holds for Nu=2u−1N_u=2u-1.

It also uses the block sieve (the manuscript's Lemma 2.9), the Siegel–Walfisz theorem, the multiplicative large sieve and Mertens' estimates. The written reconstruction of E supplies these estimates at precisely the restrictions and parameter order used below. Its separate passing grade accepts the operative sieve fragment and exact E2–E5 scopes relative to their stated classical premises. The graded comparison checks the actual interfaces; it supplies no P acceptance. In particular, its interval-restricted proxy discrepancy is for the same original α\alpha required by the signed Type II estimate.

The candidate

Fix 0<δ<1/40<\delta<1/4. Notation is that of the Type II page. Fix a nonnegative smooth Ψ\Psi supported in [1,2][1,2] and bounded below by a positive constant on a closed subinterval of (1,2)(1,2) of positive length. Take q=1/2q=1/2, ℓ=1\ell=1, λ=2\lambda=2,

c1=1,c2=65,c3=32,c4=95,s′=1r0(c1+c2),sj=s′2−jL,c_1=1,\quad c_2=\tfrac65,\quad c_3=\tfrac32,\quad c_4=\tfrac95,\qquad s'=\frac1{r_0(c_1+c_2)},\qquad s_j=s'2^{-j}L,

with r0r_0 a fixed integer such that c2s′<δc_2s'<\delta and $(r_0-1)c_1/2\ge c_2+1$. Let jxj_x be the largest jj with c1sj≥20Tc_1s_j\ge20T and Qj={p:c1sj≤log⁡p≤c2sj}\mathcal Q_j=\{p:c_1s_j\le\log p\le c_2s_j\}. At each scale jj for which [c3sj,c4sj][c_3s_j,c_4s_j] lies inside [L1/10,L1/5][L^{1/10},L^{1/5}] or inside [L3/10,L2/5][L^{3/10},L^{2/5}], the primes with logarithm in [c3sj,c4sj][c_3s_j,c_4s_j] form a small or a big group. By the prime number theorem their harmonic masses lie between fixed positive bounds and each kind has a number of groups comparable to TT, so they meet the hypotheses of the Type II page with (a,b,c,d)=(1/10,1/5,3/10,2/5)(a,b,c,d)=(1/10,1/5,3/10,2/5); they avoid the bands because c2<c3<c4<2c1c_2<c_3<c_4<2c_1, and the bands meet its hypotheses with λ=2\lambda=2 and 20T/c1≤sjx<40T/c120T/c_1\le s_{j_x}<40T/c_1. The exceptional slot of band j∗∗≥j0j_{**}\ge j_0 holds an integer vv with ec1sj∗∗≤v≤ec2sj∗∗e^{c_1s_{j_{**}}}\le v\le e^{c_2s_{j_{**}}} and P−(v)>WP^-(v)>W, where j0j_0 is a fixed lower bound depending only on the candidate geometry. Then

A(u)=aQ(u∗)W1(u),XA=∑uA(u)Ψ(u/x),Nu=2u−1.A(u)=a_Q(u_*)W_1(u),\qquad X_A=\sum_uA(u)\Psi(u/x),\qquad N_u=2u-1 .

These are the manuscript's choices; only NuN_u changes. By Proposition 7.1, for constants C,CA,CwC,C_A,C_w depending only on the early choices and for large xx,

A(u)≤LCτ(u∗),A(u)≤exp⁡(CwL) (u≍x),XA≍xLHQHP≫xL−CA,A(u)\le L^C\tau(u_*),\qquad A(u)\le\exp(C_w\sqrt L)\ (u\asymp x),\qquad X_A\asymp\frac xLH_QH_P\gg xL^{-C_A},

where HQ=∑vaQ(v)/vH_Q=\sum_va_Q(v)/v and HP=∑r∗=1W1(r)/rH_P=\sum_{r_*=1}W_1(r)/r; the comparison constants do not depend on j∗∗≥j0j_{**}\ge j_0; and on the support of A(u)Ψ(u/x)A(u)\Psi(u/x) every prime factor of uu lies in [L20,xδ][L^{20},x^\delta]. The upper end uses c2s′<δc_2s'<\delta: the band primes are at most xc2s′x^{c_2s'}, the exceptional integer is at most xc2s′x^{c_2s'}, and the group primes are below WW.

Type I distribution in the class of 1/2

For odd squarefree dd put

r(d)=∑d∣2u−1A(u)Ψ(u/x)−XAφ(d).r(d)=\sum_{d\mid2u-1}A(u)\Psi(u/x)-\frac{X_A}{\varphi(d)} .

Proposition (Type I). For every fixed ϑ<1/2\vartheta<1/2 and D>0D>0,

∑d≤xϑd odd, squarefree∣r(d)∣≪xL−D+XAL−18.\sum_{\substack{d\le x^\vartheta\\ d\text{ odd, squarefree}}}|r(d)| \ll xL^{-D}+X_AL^{-18}.

Proof. If a prime ll divides both dd and uu, then 2u−1≡−1(modl)2u-1\equiv-1\pmod l, so d∤2u−1d\nmid2u-1. For (u,d)=1(u,d)=1, d∣2u−1d\mid2u-1 holds exactly when u≡2ˉ(modd)u\equiv\bar2\pmod d, where 2ˉ=(d+1)/2\bar2=(d+1)/2 is the inverse of 22, a unit class. By orthogonality,

∑d∣2u−1A(u)Ψ(u/x)=1φ(d)∑χ mod dχ(2ˉ)‾∑uA(u)Ψ(u/x)χ(u).\sum_{d\mid2u-1}A(u)\Psi(u/x) =\frac1{\varphi(d)}\sum_{\chi\bmod d}\overline{\chi(\bar2)} \sum_uA(u)\Psi(u/x)\chi(u).

The principal character gives φ(d)−1∑(u,d)=1A(u)Ψ(u/x)\varphi(d)^{-1}\sum_{(u,d)=1}A(u)\Psi(u/x). Replacing it by XA/φ(d)X_A/\varphi(d) costs in total at most

∑uA(u)Ψ(u/x)∑d≤xϑ(d,u)>1μ2(d)φ(d)≤XAmax⁡u∑l∣u1l−1∑d′≤xμ2(d′)φ(d′)≪XAL−18,\sum_uA(u)\Psi(u/x)\sum_{\substack{d\le x^\vartheta\\(d,u)>1}} \frac{\mu^2(d)}{\varphi(d)} \le X_A\max_u\sum_{l\mid u}\frac1{l-1} \sum_{d'\le x}\frac{\mu^2(d')}{\varphi(d')} \ll X_AL^{-18},

because every prime factor of a supported uu is at least L20L^{20}, there are O(L/log⁡L)O(L/\log L) of them, and the last sum is O(L)O(L).

The nonprincipal characters contribute at most φ(d)−1∑χ≠χ0∣∑uA(u)Ψ(u/x)χ(u)∣\varphi(d)^{-1}\sum_{\chi\ne\chi_0}|\sum_uA(u)\Psi(u/x)\chi(u)|, since ∣χ(2ˉ)∣=1|\chi(\bar2)|=1; this quantity does not involve the unit class. Extract one pure slot of band 00 to write A(u)=∑pr=u, p∈Q0b(r)A(u)=\sum_{pr=u,\ p\in\mathcal Q_0}b(r) with 0≤b(r)≤LO(1)τ(r)0\le b(r)\le L^{O(1)}\tau(r); the extracted prime is not a group prime, so W1(u)=W1(r)W_1(u)=W_1(r). Split pp and rr into dyads P,UP,U with PU≍xPU\asymp x; for a fixed a0>0a_0>0 every contributing dyad has xa0≪P,U≪x1−a0x^{a_0}\ll P,U\ll x^{1-a_0}. A nonprincipal χ mod d\chi\bmod d is induced by a primitive χ∗\chi^* modulo some f>1f>1 with d=hfd=hf and (h,f)=1(h,f)=1, acting as χ∗\chi^* together with (p,h)=(r,h)=1(p,h)=(r,h)=1. For conductors f≍R>LC′f\asymp R>L^{C'}, separate Ψ(pr/x)\Psi(pr/x) by Mellin inversion at bounded integrated cost; the multiplicative large sieve and Cauchy's inequality give

∑f≍R1φ(f)∑χ∗ mod f∗∣∑p≍Papχ∗(p)∣∣∑r≍Ubrχ∗(r)∣≪xLO(1)(1R+1P+1U+Rx),\sum_{f\asymp R}\frac1{\varphi(f)}\sum_{\chi^*\bmod f}^{*} \Bigl|\sum_{p\asymp P}a_p\chi^*(p)\Bigr|\Bigl|\sum_{r\asymp U}b_r\chi^*(r)\Bigr| \ll xL^{O(1)}\Bigl(\frac1R+\frac1{\sqrt P}+\frac1{\sqrt U} +\frac R{\sqrt x}\Bigr),

which, summed over dyads, over hh with weight 1/φ(h)1/\varphi(h) and over $R\le x^\vartheta$, saves any fixed power of LL once C′C' is large. For $1<f\le 2L^{C'}$, fix rr and apply the Siegel–Walfisz theorem with partial summation to the sum over pp with the cutoff Ψ(pr/x)\Psi(pr/x), which saves any fixed power of LL; the primes p∣hp\mid h are O(1)O(1) in number, since they exceed xa0x^{a_0} and h≤xϑh\le x^\vartheta, and cost x1−a0LO(1)x^{1-a_0}L^{O(1)} in total. □\square

This is the manuscript's Proposition 7.2 with the unit class −2ˉ-\bar2 replaced by 2ˉ\bar2; every estimate after orthogonality is in absolute value.

The preliminary sieve

Write V(y)=∏p≤y(1−1/p)V(y)=\prod_{p\le y}(1-1/p), V1(y)=∏3≤p≤y(1−1/(p−1))V_1(y)=\prod_{3\le p\le y}(1-1/(p-1)) and S=2∏p≥3(1−(p−1)−2)>0\mathfrak S=2\prod_{p\ge3}(1-(p-1)^{-2})>0, so that $V(y)\sim e^{-\gamma_E}/\log y$ and V1(y)∼SV(y)V_1(y)\sim\mathfrak SV(y). Fix 0<κ<1/500<\kappa<1/50 and then a small fixed b1>0b_1>0; put b∗=b1/3b_*=b_1/3, choose j∗∗≥j0j_{**}\ge j_0 with c2s′2−j∗∗<b∗/4c_2s'2^{-j_{**}}<b_*/4 (so that η∗<b∗/4\eta_*<b_*/4), and take h=2⌊1/(40b1)⌋h=2\lfloor1/(40b_1)\rfloor and ϑ=1/2−κ/2\vartheta=1/2-\kappa/2. For small b1b_1, hh is large enough for the block sieve and b1(4h+2)<ϑb_1(4h+2)<\vartheta.

Every Nu=2u−1N_u=2u-1 is odd. Apply the block sieve to the integers uu with weight A(u)Ψ(u/x)A(u)\Psi(u/x), with the bad conditions p∣2u−1p\mid2u-1 for the odd primes $p\le x^{b_1}$. For squarefree odd dd the weight on which all conditions at p∣dp\mid d hold is XA/φ(d)+r(d)X_A/\varphi(d)+r(d), so the density is g(p)=1/(p−1)g(p)=1/(p-1), which satisfies g(3)=1/2g(3)=1/2 and ∑w<p≤w2g(p)≪1\sum_{w<p\le w^2}g(p)\ll1. With the Type I bound at level xϑx^\vartheta and D>CA+10D>C_A+10,

∑P−(2u−1)>xb1A(u)Ψ(u/x)≥SXAL{e−γEb1(1−O(e−c/b1))+o(1)},\sum_{P^-(2u-1)>x^{b_1}}A(u)\Psi(u/x) \ge\frac{\mathfrak SX_A}L\Bigl\{\frac{e^{-\gamma_E}}{b_1} \bigl(1-O(e^{-c/b_1})\bigr)+o(1)\Bigr\},

with constants uniform for small b1b_1 and 0<κ<1/500<\kappa<1/50. This is the manuscript's (7.11); the density 1/(p−1)1/(p-1) is the same for both signs, because 2u±1≡0(modp)2u\pm1\equiv0\pmod p each fix one unit class of uu.

Composites away from balance

Fix a finite mesh of bins (γ,γ′](\gamma,\gamma'] partitioning (b1,1/2−κ](b_1,1/2-\kappa], chosen below. Write Iγ(m)=1P−(m)>xγI_\gamma(m)=\mathbf 1_{P^-(m)>x^\gamma} and Ipr(m)=1m primeI_{\rm pr}(m)=\mathbf 1_{m\text{ prime}}, and let BγB_\gamma, BprB_{\rm pr} be their cell proxies at precision ΔL=L−S\Delta_L=L^{-S}: on a cell CY=(Y,eΔLY]C_Y=(Y,e^{\Delta_L}Y] the proxy of a test II is cI(CY)1P−(m)>Wc_I(C_Y)\mathbf 1_{P^-(m)>W}, where cI(CY)c_I(C_Y) is the number of m∈CYm\in C_Y with I(m)=1I(m)=1 divided by the number of WW-rough m∈CYm\in C_Y. By Lemma 7.3, 0≤BI≤10\le B_I\le1, and for any fixed BB the restricted differences (I−BI)1K(I-B_I)\mathbf 1_K satisfy (DB)(\mathrm D_B) once S>2B+3S>2B+3, uniformly for intervals KK inside dyads of [xb1/4,x1−b1/4][x^{b_1/4},x^{1-b_1/4}].

A composite 2u−12u-1 counted above whose least prime factor pp lies in the bin (xγ,xγ′](x^\gamma,x^{\gamma'}] has m=(2u−1)/pm=(2u-1)/p with P−(m)>xγP^-(m)>x^\gamma, so the composites of this bin contribute at most

∑mp=2u−1xγ<p≤xγ′ primeA(u)Ψ(u/x) Iγ(m).\sum_{\substack{mp=2u-1\\ x^\gamma<p\le x^{\gamma'}\text{ prime}}} A(u)\Psi(u/x)\,I_\gamma(m).

All contributing dyads of mm and pp lie in [xb∗,x1−b∗][x^{b_*},x^{1-b_*}]. Apply the signed Type II estimate with α=(Iγ−Bγ)1K\alpha=(I_\gamma-B_\gamma)\mathbf 1_K, KK the cofactor range within a dyad, and β\beta the prime indicator of the bin within a dyad: replacing IγI_\gamma by BγB_\gamma costs o(XA/L)o(X_A/L) in total. By the bound (7.17) of Lemma 7.4,

cγ(m)≤sup⁡γ≤a≤γ′Dγ(1−a)+o(1)LV(W),c_\gamma(m)\le\frac{\sup_{\gamma\le a\le\gamma'}D_\gamma(1-a)+o(1)}{LV(W)},

where DγD_\gamma is the Buchstab density (7.15) of the manuscript. For a prime p>Wp>W, P−((2u−1)/p)>WP^-((2u-1)/p)>W if and only if P−(2u−1)>WP^-(2u-1)>W, so the bin contributes at most that constant over LV(W)LV(W) times

∑xγ<p≤xγ′ ∑p∣2u−1P−(2u−1)>WA(u)Ψ(u/x).\sum_{x^\gamma<p\le x^{\gamma'}}\ \sum_{\substack{p\mid2u-1\\ P^-(2u-1)>W}} A(u)\Psi(u/x).

For each pp, sieve the odd primes up to WW with base mass XA/(p−1)X_A/(p-1), density 1/(l−1)1/(l-1), remainders r(pd)r(pd) and h=2⌈T2⌉h=2\lceil T^2\rceil. All products pdpd are at most x1/2−κ+o(1)<xϑx^{1/2-\kappa+o(1)}<x^\vartheta, and distinct pairs (p,d)(p,d) give distinct products, pp being their only prime factor above WW. The Type I bound therefore gives

∑xγ<p≤xγ′ ∑p∣2u−1P−(2u−1)>WA(u)Ψ(u/x)=XAV1(W)∑xγ<p≤xγ′1p−1+o(XAV(W)),\sum_{x^\gamma<p\le x^{\gamma'}}\ \sum_{\substack{p\mid2u-1\\ P^-(2u-1)>W}} A(u)\Psi(u/x)=X_AV_1(W)\sum_{x^\gamma<p\le x^{\gamma'}}\frac1{p-1} +o(X_AV(W)),

and since the reciprocal sum tends to log⁡(γ′/γ)\log(\gamma'/\gamma), the bin contributes at most

SXAL{sup⁡γ≤a≤γ′Dγ(1−a)log⁡(γ′/γ)+o(1)}.\frac{\mathfrak SX_A}L\Bigl\{\sup_{\gamma\le a\le\gamma'}D_\gamma(1-a) \log(\gamma'/\gamma)+o(1)\Bigr\}.

By the joint continuity in Lemma 7.4, a fine enough fixed mesh makes the sum of these constants at most ∫b11/2−κDα(1−α) dα/α+1/10\int_{b_1}^{1/2-\kappa}D_\alpha(1-\alpha)\,d\alpha/\alpha+1/10. The identity (7.18), ∫b11/2Dα(1−α) dα/α=Db1(1)−1\int_{b_1}^{1/2}D_\alpha(1-\alpha)\,d\alpha/\alpha=D_{b_1}(1)-1, and the bound (7.19), Db1(1)≤e−γEb1−1(1+O(e−c/b1))D_{b_1}(1)\le e^{-\gamma_E}b_1^{-1}(1+O(e^{-c/b_1})), then leave

∑2u−1 prime, orP−(2u−1)>x1/2−κA(u)Ψ(u/x)≥SXAL{1−110−O(b1−1e−c/b1)+o(1)}≥SXA2L\sum_{\substack{2u-1\text{ prime, or}\\ P^-(2u-1)>x^{1/2-\kappa}}}A(u)\Psi(u/x) \ge\frac{\mathfrak SX_A}L\Bigl\{1-\frac1{10}-O(b_1^{-1}e^{-c/b_1})+o(1)\Bigr\} \ge\frac{\mathfrak SX_A}{2L}

once b1b_1 is small enough.

Balanced composites

A composite 2u−1≪x2u-1\ll x with P−(2u−1)>x1/2−κP^-(2u-1)>x^{1/2-\kappa} has exactly two prime factors, as 3(1/2−κ)>13(1/2-\kappa)>1, and both lie in Bκ=[x1/2−2κ,x1/2+2κ]\mathcal B_\kappa=[x^{1/2-2\kappa},x^{1/2+2\kappa}] for large xx. Overcount by ordered pairs of primes m,n∈Bκm,n\in\mathcal B_\kappa with mn=2u−1mn=2u-1. Replace Ipr(m)I_{\rm pr}(m) by Bpr(m)B_{\rm pr}(m) with the signed Type II estimate, then Ipr(n)I_{\rm pr}(n) by Bpr(n)B_{\rm pr}(n) with the roles of the two factors exchanged, the remaining coefficient Bpr(m)B_{\rm pr}(m) being bounded by one. Since Bpr≤C/(LV(W))B_{\rm pr}\le C/(LV(W)) on Bκ\mathcal B_\kappa by (7.16), with CC absolute for 0<κ<1/500<\kappa<1/50, the balanced composites contribute o(XA/L)o(X_A/L) plus

CL2V(W)2∑m,n∈Bκ, mn=2u−1P−(m)>W, P−(n)>WA(u)Ψ(u/x).\frac C{L^2V(W)^2}\sum_{\substack{m,n\in\mathcal B_\kappa,\ mn=2u-1\\ P^-(m)>W,\ P^-(n)>W}}A(u)\Psi(u/x).

Balanced dyadic bound. For dyads m≍M1m\asymp M_1 and n≍M2n\asymp M_2 intersecting Bκ\mathcal B_\kappa, with M1M2≍xM_1M_2\asymp x and 0<κ<1/500<\kappa<1/50,

∑m,n∈Bκ, m≍M1, n≍M2, mn=2u−1P−(m)>W, P−(n)>WA(u)Ψ(u/x)≪XAV(W)2,\sum_{\substack{m,n\in\mathcal B_\kappa,\ m\asymp M_1,\ n\asymp M_2,\ mn=2u-1\\ P^-(m)>W,\ P^-(n)>W}} A(u)\Psi(u/x)\ll X_AV(W)^2,

with a constant depending only on δ,r0,Ψ\delta,r_0,\Psi, the group geometry and the fixed j′,θj',\theta below, not on κ\kappa, b1b_1, j∗∗j_{**}, SS or the analytic parameters.

The balance restriction supplies Mi≪x0.54M_i\ll x^{0.54}, which is used in the box-error estimate below. A product-size condition alone is not asserted to imply this bound.

The conditional-chain examination records refuted-as-stated for the frozen isolated formulation without the balanced range, using m=1m=1 to lose one roughness factor. It records refutation-failed for the balanced specialization consumed here. The explicit balanced-range statement and box-error qualification above differ from the frozen wording; its exact subject and witness are retained with the examination.

Proof. Choose a large fixed j′j' and θ\theta with

c2s′2−j′<θ<c1s′2−j′+1,10θ≤120,∑j≥j′r0c2s′2−j≤125,c_2s'2^{-j'}<\theta<c_1s'2^{-j'+1},\qquad 10\theta\le\frac1{20},\qquad \sum_{j\ge j'}r_0c_2s'2^{-j}\le\frac1{25},

possible because c2<2c1c_2<2c_1, and enlarge j0j_0 so that j0≥j′j_0\ge j'; the micro bands are those with j≥j′j\ge j', and their harmonic mass HQmicH_Q^{\rm mic} satisfies HQmic≪HQH_Q^{\rm mic}\ll H_Q. An assignment consists of complete ordered lists in the micro bands, the exceptional slot included, and one marked prime in each group, with weight λ=∏j≥j′(1/r0!)∏g(1/Vg)\lambda=\prod_{j\ge j'}(1/r_0!)\prod_g(1/V_g); let D1D_1 be the product of its entries. Then

D1≤x1/20,∑assgnλD1=HQmic,∑assgnλ≤x1/20HQmic.D_1\le x^{1/20},\qquad \sum_{\rm assgn}\frac\lambda{D_1}=H_Q^{\rm mic},\qquad \sum_{\rm assgn}\lambda\le x^{1/20}H_Q^{\rm mic}.

Write s=∣S∣+∣B∣s=|\mathcal S|+|\mathcal B| and ω(u)=∑gωg(u)\omega(u)=\sum_g\omega_g(u). For each assignment, ban every odd prime l≤xθl\le x^\theta that is not a group prime and does not divide D1D_1, and ban each group prime not dividing D1D_1 independently with probability 1−q1-q. Expanding A(u)A(u) into lists and marks, every non-group prime factor of uu below xθx^\theta divides D1D_1: the omitted bands contain only pure primes above xθx^\theta, and the entire exceptional integer is in D1D_1. Its prime divisors need not lie in any prime band. The group part of D1D_1 consists of exactly one mark per group, so the expected value of the permissions is the damping qω(u)−sq^{\omega(u)-s} of W1W_1. For a fixed residual product the normalized number of omitted pure-prime lists is at most one, since its contribution in each band is a product of reciprocal multiplicity factorials. Dropping those residual restrictions gives the majorant

A(u)≤∑assgnλ 1D1∣u Emask1{l∤u for every banned l},A(u)\le\sum_{\rm assgn}\lambda\,\mathbf 1_{D_1\mid u}\, \mathbb E_{\rm mask}\mathbf 1_{\{l\nmid u\text{ for every banned }l\}},

which concerns uu alone and is the manuscript's (7.27).

Fix an assignment and a mask. The integer D1D_1 is odd, because its entries are primes at least L20L^{20} and the exceptional integer, all of whose prime factors exceed WW. So D1∣uD_1\mid u and mn=2u−1mn=2u-1 give

mn≡−1(modD1).mn\equiv-1\pmod{D_1}.

For an odd prime l≤xθl\le x^\theta with l∤D1l\nmid D_1 the bad events are mn≡0(modl)mn\equiv0\pmod l when l≤Wl\le W (roughness of mm and nn), and mn≡−1(modl)mn\equiv-1\pmod l when ll is banned, which is l∣ul\mid u because ll is odd. These residue sets are disjoint and contain 2l−12l-1 and l−1l-1 pairs. Put ν(l)=(2l−1)1l≤W+(l−1)1l banned\nu(l)=(2l-1)\mathbf 1_{l\le W}+(l-1)\mathbf 1_{l\text{ banned}} and g(l)=ν(l)/l2≤3/lg(l)=\nu(l)/l^2\le3/l, bounded away from one for l≥3l\ge3. For a squarefree product dd of these primes, the congruence modulo D1D_1 leaves, for each unit m mod D1m\bmod D_1, exactly one n mod D1n\bmod D_1, also when D1D_1 has square factors; with the Chinese remainder theorem there are exactly φ(D1)ν(d)\varphi(D_1)\nu(d) admissible residue pairs modulo D1dD_1d. Each pair has lattice count in the box equal to its area term with error O(1+(M1+M2)/(D1d))O(1+(M_1+M_2)/(D_1d)), so the remainders up to D=x10θD=x^{10\theta} sum to

≪LO(1)((M1+M2)D+D1D2)≤LO(1)((M1+M2)x1/20+D1x1/10).\ll L^{O(1)}\bigl((M_1+M_2)D+D_1D^2\bigr) \le L^{O(1)}\bigl((M_1+M_2)x^{1/20}+D_1x^{1/10}\bigr).

The upper-bound block sieve with h=2h=2 gives the main term ≪M1M2 φ(D1)D1−2∏l(1−g(l))\ll M_1M_2\,\varphi(D_1)D_1^{-2}\prod_l(1-g(l)), the product over the odd primes l≤xθl\le x^\theta not dividing D1D_1. A banned prime below WW has factor (1−1/l)(1−2/l)(1-1/l)(1-2/l) and a banned prime above WW has factor 1−1/l+1/l21-1/l+1/l^2, each at most (1−1/l)1+21l≤W(1+O(l−2))(1-1/l)^{1+2\mathbf 1_{l\le W}}(1+O(l^{-2})); an allowed group prime has factor (1−1/l)2(1-1/l)^2. Hence

∏3≤l≤xθl∤D1(1−g(l))≤CV(W)2V(xθ)∏l∣D1(1−1/l)−3∏p allowedp∤D1(1−1/p)−1.\prod_{\substack{3\le l\le x^\theta\\ l\nmid D_1}}(1-g(l)) \le CV(W)^2V(x^\theta)\prod_{l\mid D_1}(1-1/l)^{-3} \prod_{\substack{p\text{ allowed}\\ p\nmid D_1}}(1-1/p)^{-1}.

The product over l∣D1l\mid D_1 is bounded, since those primes are at least L20L^{20} and D1≤x1/20D_1\le x^{1/20}, and the mask expectation of the last product is ∏p∤D1(1+q/(p−1))≤HP\prod_{p\nmid D_1}(1+q/(p-1))\le H_P, the product over group primes, by the manuscript's (7.6). Summing the main terms over assignments with φ(D1)D1−2≤D1−1\varphi(D_1)D_1^{-2}\le D_1^{-1} gives $\ll xV(W)^2V(x^\theta)H_Q^{\rm mic}H_P\ll X_AV(W)^2$, and the remainders give $\ll x^{0.64}L^{O(1)}H_Q^{\rm mic}=o(X_AV(W)^2)$, using Mi≪x0.54M_i\ll x^{0.54} and XAV(W)2≍xHQHP/L2X_AV(W)^2\asymp xH_QH_P/L^2. □\square

There are O(κL+1)O(\kappa L+1) dyads for mm in Bκ\mathcal B_\kappa and O(1)O(1) for nn given mm, so the balanced composites contribute at most

Cbal(κ+L−1)XAL+o(XA/L),C_{\rm bal}(\kappa+L^{-1})\frac{X_A}L+o(X_A/L),

with CbalC_{\rm bal} depending only on δ,r0,Ψ,j′,θ\delta,r_0,\Psi,j',\theta and the group geometry. The residue counts are those of the manuscript's (7.30)–(7.31): there the congruences read mn≡1mn\equiv1 modulo D1D_1 and modulo each banned prime, with the same numbers of residue pairs.

The count and Hypothesis A+

The choices are made in the manuscript's order.

  1. Fix δ\delta, Ψ\Psi, r0r_0 and the band and group geometry; the finite prefix of bands used for the lower bound of XAX_A; then j′j' and θ\theta; and j0j_0 covering both.
  2. Fix κ∈(0,1/50)\kappa\in(0,1/50) with Cbalκ<S/4C_{\rm bal}\kappa<\mathfrak S/4, possible because CbalC_{\rm bal} does not depend on κ\kappa.
  3. Fix b1b_1 small enough for the preliminary sieve and for the subtraction above; set b∗=b1/3b_*=b_1/3; fix j∗∗j_{**} with c2s′2−j∗∗<b∗/4c_2s'2^{-j_{**}}<b_*/4; fix the bin mesh.
  4. Fix the Type II saving D∗D_* so that every replacement error, after the dyadic sums, is o(XA/L)o(X_A/L). The Type II proof then fixes K0K_0, D0D_0 and, through (P), the discrepancy exponent BB.
  5. Fix S>2B+3S>2B+3 in Lemma 7.3 and the prime-number-theorem accuracies, and let x→∞x\to\infty.

The coefficient bound of the proxies does not depend on SS, so step 5 does not feed back into step 4. For all large real xx,

∑2u−1 primeA(u)Ψ(u/x)≥SXA2L−Cbal(κ+1L)XAL−o(XAL)≥SXA5L.\sum_{2u-1\text{ prime}}A(u)\Psi(u/x)\ge\frac{\mathfrak SX_A}{2L} -C_{\rm bal}\Bigl(\kappa+\frac1L\Bigr)\frac{X_A}L-o\Bigl(\frac{X_A}L\Bigr) \ge\frac{\mathfrak SX_A}{5L}.

After enlarging CwC_w to absorb the fixed bound on Ψ\Psi, each summand is at most exp⁡(CwL)\exp(C_w\sqrt L). Since XA≥cAxL−CAX_A\ge c_AxL^{-C_A} and u↦2u−1u\mapsto2u-1 is injective, at least (ScA/5) xL−CA−1exp⁡(−CwL)(\mathfrak Sc_A/5)\,xL^{-C_A-1}\exp(-C_w\sqrt L) distinct primes p=2u−1p=2u-1 occur. As Ψ(u/x)≠0\Psi(u/x)\ne0 forces x≤u≤2xx\le u\le2x, they satisfy 2x−1≤p≤4x−12x-1\le p\le4x-1, and p+1=2up+1=2u with every prime factor of uu at most xδx^\delta, so P+(p+1)=max⁡(2,P+(u))≤xδP^+(p+1)=\max(2,P^+(u))\le x^\delta. This proves:

Successor count, assuming (P) and (E). For every fixed 0<δ<1/40<\delta<1/4 there are c,CA,Cw>0c,C_A,C_w>0 such that for all sufficiently large real xx

#{p prime: 2x−1≤p≤4x−1, P+(p+1)≤xδ}≥c x(log⁡x)−CA−1exp⁡(−Cwlog⁡x).\#\{p\text{ prime}:\ 2x-1\le p\le4x-1,\ P^+(p+1)\le x^\delta\} \ge c\,x(\log x)^{-C_A-1}\exp\bigl(-C_w\sqrt{\log x}\bigr).

Hypothesis A+, assuming (P) and (E). Given 0<δ<1/40<\delta<1/4 and η>0\eta>0, the quantity ηL−(CA+1)log⁡L−CwL+log⁡c\eta L-(C_A+1)\log L-C_w\sqrt L+\log c tends to infinity, so the successor count at x=yx=y gives at least y1−ηy^{1-\eta} primes p≤4y−1<5yp\le4y-1<5y with P+(p+1)≤yδP^+(p+1)\le y^\delta, for every real yy beyond a threshold depending on δ\delta and η\eta. No uniformity as δ→0\delta\to0 and no effective threshold is claimed, and none is needed.

The counted primes lie inside the range 2x−2<p≤5x2x-2<p\le5x of Li and Zhuang's Theorem 1.4, which states this count under the assumption that the manuscript's argument is correct.