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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 p with P+(p+1)≤xδ, and from it to Hypothesis
A+. The extraction is OpenAI's, from Section 7 of the
weighted-dilation manuscript;
running it on primes 2u−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 u or ordinary factor
tests; the only occurrence of Nu is a size relation in (7.17).
Proposition 7.1 (candidate mass) concerns A, XA and the prime
factors of u 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=Nu; its proof uses Nu only
through Nu≍x, which holds for Nu=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 required by the signed Type II estimate.
The candidate
Fix 0<δ<1/4. Notation is that of the
Type II page. Fix a
nonnegative smooth Ψ supported in [1,2] and bounded below by a positive
constant on a closed subinterval of (1,2) of positive length. Take q=1/2,
ℓ=1, λ=2,
with r0 a fixed integer such that c2s′<δ and $(r_0-1)c_1/2\ge
c_2+1$. Let jx be the largest j with c1sj≥20T and
Qj={p:c1sj≤logp≤c2sj}. At each scale j for which
[c3sj,c4sj] lies inside [L1/10,L1/5] or inside
[L3/10,L2/5], the primes with logarithm in [c3sj,c4sj] 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 T, so they meet the hypotheses of the Type II page with
(a,b,c,d)=(1/10,1/5,3/10,2/5); they avoid the bands because
c2<c3<c4<2c1, and the bands meet its hypotheses with λ=2 and
20T/c1≤sjx<40T/c1. The exceptional slot of band j∗∗≥j0
holds an integer v with ec1sj∗∗≤v≤ec2sj∗∗ and
P−(v)>W, where j0 is a fixed lower bound depending only on the candidate
geometry. Then
A(u)=aQ(u∗)W1(u),XA=u∑A(u)Ψ(u/x),Nu=2u−1.
These are the manuscript's choices; only Nu changes. By Proposition 7.1,
for constants C,CA,Cw depending only on the early choices and for large
x,
where HQ=∑vaQ(v)/v and HP=∑r∗=1W1(r)/r; the comparison
constants do not depend on j∗∗≥j0; and on the support of
A(u)Ψ(u/x) every prime factor of u lies in [L20,xδ]. The upper
end uses c2s′<δ: the band primes are at most xc2s′, the
exceptional integer is at most xc2s′, and the group primes are below W.
Type I distribution in the class of 1/2
For odd squarefree d put
r(d)=d∣2u−1∑A(u)Ψ(u/x)−φ(d)XA.
Proposition (Type I). For every fixed ϑ<1/2 and D>0,
d≤xϑd odd, squarefree∑∣r(d)∣≪xL−D+XAL−18.
Proof. If a prime l divides both d and u, then 2u−1≡−1(modl),
so d∤2u−1. For (u,d)=1, d∣2u−1 holds exactly when
u≡2ˉ(modd), where 2ˉ=(d+1)/2 is the inverse of 2, a unit
class. By orthogonality,
because every prime factor of a supported u is at least L20, there are
O(L/logL) of them, and the last sum is O(L).
The nonprincipal characters contribute at most
φ(d)−1∑χ=χ0∣∑uA(u)Ψ(u/x)χ(u)∣, since
∣χ(2ˉ)∣=1; this quantity does not involve the unit class. Extract one
pure slot of band 0 to write A(u)=∑pr=u,p∈Q0b(r) with
0≤b(r)≤LO(1)τ(r); the extracted prime is not a group prime, so
W1(u)=W1(r). Split p and r into dyads P,U with PU≍x; for a
fixed a0>0 every contributing dyad has xa0≪P,U≪x1−a0. A
nonprincipal χmodd is induced by a primitive χ∗ modulo some
f>1 with d=hf and (h,f)=1, acting as χ∗ together with
(p,h)=(r,h)=1. For conductors f≍R>LC′, separate Ψ(pr/x) by
Mellin inversion at bounded integrated cost; the multiplicative large sieve and
Cauchy's inequality give
which, summed over dyads, over h with weight 1/φ(h) and over $R\le
x^\vartheta$, saves any fixed power of L once C′ is large. For $1<f\le
2L^{C'}$, fix r and apply the Siegel–Walfisz theorem with partial summation
to the sum over p with the cutoff Ψ(pr/x), which saves any fixed power of
L; the primes p∣h are O(1) in number, since they exceed xa0 and
h≤xϑ, and cost x1−a0LO(1) in total. □
This is the manuscript's Proposition 7.2 with the unit class −2ˉ replaced
by 2ˉ; every estimate after orthogonality is in absolute value.
The preliminary sieve
Write V(y)=∏p≤y(1−1/p), V1(y)=∏3≤p≤y(1−1/(p−1)) and
S=2∏p≥3(1−(p−1)−2)>0, so that $V(y)\sim
e^{-\gamma_E}/\log y$ and V1(y)∼SV(y). Fix 0<κ<1/50 and
then a small fixed b1>0; put b∗=b1/3, choose j∗∗≥j0 with
c2s′2−j∗∗<b∗/4 (so that η∗<b∗/4), and take
h=2⌊1/(40b1)⌋ and ϑ=1/2−κ/2. For small b1, h
is large enough for the block sieve and b1(4h+2)<ϑ.
Every Nu=2u−1 is odd. Apply the block sieve to the integers u with weight
A(u)Ψ(u/x), with the bad conditions p∣2u−1 for the odd primes $p\le
x^{b_1}$. For squarefree odd d the weight on which all conditions at p∣d
hold is XA/φ(d)+r(d), so the density is g(p)=1/(p−1), which satisfies
g(3)=1/2 and ∑w<p≤w2g(p)≪1. With the Type I bound at level
xϑ and D>CA+10,
with constants uniform for small b1 and 0<κ<1/50. This is the
manuscript's (7.11); the density 1/(p−1) is the same for both signs, because
2u±1≡0(modp) each fix one unit class of u.
Composites away from balance
Fix a finite mesh of bins (γ,γ′] partitioning (b1,1/2−κ],
chosen below. Write Iγ(m)=1P−(m)>xγ and
Ipr(m)=1m prime, and let Bγ, Bpr be
their cell proxies at precision ΔL=L−S: on a cell
CY=(Y,eΔLY] the proxy of a test I is
cI(CY)1P−(m)>W, where cI(CY) is the number of m∈CY
with I(m)=1 divided by the number of W-rough m∈CY. By Lemma 7.3,
0≤BI≤1, and for any fixed B the restricted differences
(I−BI)1K satisfy (DB) once S>2B+3, uniformly for
intervals K inside dyads of [xb1/4,x1−b1/4].
A composite 2u−1 counted above whose least prime factor p lies in the bin
(xγ,xγ′] has m=(2u−1)/p with P−(m)>xγ, so the
composites of this bin contribute at most
mp=2u−1xγ<p≤xγ′ prime∑A(u)Ψ(u/x)Iγ(m).
All contributing dyads of m and p lie in [xb∗,x1−b∗]. Apply the
signed Type II estimate with α=(Iγ−Bγ)1K, K the
cofactor range within a dyad, and β the prime indicator of the bin within
a dyad: replacing Iγ by Bγ costs o(XA/L) in total. By the
bound (7.17) of Lemma 7.4,
cγ(m)≤LV(W)supγ≤a≤γ′Dγ(1−a)+o(1),
where Dγ is the Buchstab density (7.15) of the manuscript. For a prime
p>W, P−((2u−1)/p)>W if and only if P−(2u−1)>W, so the bin contributes at
most that constant over LV(W) times
xγ<p≤xγ′∑p∣2u−1P−(2u−1)>W∑A(u)Ψ(u/x).
For each p, sieve the odd primes up to W with base mass XA/(p−1),
density 1/(l−1), remainders r(pd) and h=2⌈T2⌉. All products
pd are at most x1/2−κ+o(1)<xϑ, and distinct pairs (p,d)
give distinct products, p being their only prime factor above W. The Type I
bound therefore gives
and since the reciprocal sum tends to log(γ′/γ), the bin
contributes at most
LSXA{γ≤a≤γ′supDγ(1−a)log(γ′/γ)+o(1)}.
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. The identity
(7.18), ∫b11/2Dα(1−α)dα/α=Db1(1)−1, and
the bound (7.19), Db1(1)≤e−γEb1−1(1+O(e−c/b1)), then
leave
A composite 2u−1≪x with P−(2u−1)>x1/2−κ has exactly two prime
factors, as 3(1/2−κ)>1, and both lie in
Bκ=[x1/2−2κ,x1/2+2κ] for large x. Overcount
by ordered pairs of primes m,n∈Bκ with mn=2u−1. Replace
Ipr(m) by Bpr(m) with the signed Type II estimate, then
Ipr(n) by Bpr(n) with the roles of the two factors exchanged,
the remaining coefficient Bpr(m) being bounded by one. Since
Bpr≤C/(LV(W)) on Bκ by (7.16), with C absolute
for 0<κ<1/50, the balanced composites contribute o(XA/L) plus
with a constant depending only on δ,r0,Ψ, the group geometry and the
fixed j′,θ below, not on κ, b1, j∗∗, S or the analytic
parameters.
The balance restriction supplies Mi≪x0.54, 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=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.
possible because c2<2c1, and enlarge j0 so that j0≥j′; the
micro bands are those with j≥j′, and their harmonic mass HQmic
satisfies HQmic≪HQ. 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); let D1 be the product of
its entries. Then
Write s=∣S∣+∣B∣ and ω(u)=∑gωg(u).
For each assignment, ban every odd prime l≤xθ that is not a group
prime and does not divide D1, and ban each group prime not dividing D1
independently with probability 1−q. Expanding A(u) into lists and marks,
every non-group prime factor of u below xθ divides D1: the
omitted bands contain only pure primes above xθ, and the entire
exceptional integer is in D1. Its prime divisors need not lie in any prime
band. The group part of D1 consists of exactly one mark per group, so the
expected value of the permissions is the damping qω(u)−s of W1.
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)≤assgn∑λ1D1∣uEmask1{l∤u for every banned l},
which concerns u alone and is the manuscript's (7.27).
Fix an assignment and a mask. The integer D1 is odd, because its entries are
primes at least L20 and the exceptional integer, all of whose prime
factors exceed W. So D1∣u and mn=2u−1 give
mn≡−1(modD1).
For an odd prime l≤xθ with l∤D1 the bad events are
mn≡0(modl) when l≤W (roughness of m and n), and
mn≡−1(modl) when l is banned, which is l∣u because l is odd.
These residue sets are disjoint and contain 2l−1 and l−1 pairs. Put
ν(l)=(2l−1)1l≤W+(l−1)1l banned and
g(l)=ν(l)/l2≤3/l, bounded away from one for l≥3. For a squarefree
product d of these primes, the congruence modulo D1 leaves, for each unit
mmodD1, exactly one nmodD1, also when D1 has square factors; with
the Chinese remainder theorem there are exactly φ(D1)ν(d) admissible
residue pairs modulo D1d. Each pair has lattice count in the box equal to its
area term with error O(1+(M1+M2)/(D1d)), so the remainders up to
D=x10θ sum to
The upper-bound block sieve with h=2 gives the main term
≪M1M2φ(D1)D1−2∏l(1−g(l)), the product over the odd
primes l≤xθ not dividing D1. A banned prime below W has factor
(1−1/l)(1−2/l) and a banned prime above W has factor 1−1/l+1/l2, each at
most (1−1/l)1+21l≤W(1+O(l−2)); an allowed group prime
has factor (1−1/l)2. Hence
The product over l∣D1 is bounded, since those primes are at least
L20 and D1≤x1/20, and the mask expectation of the last product is
∏p∤D1(1+q/(p−1))≤HP, the product over group primes, by the
manuscript's (7.6). Summing the main terms over assignments with
φ(D1)D1−2≤D1−1 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≪x0.54 and
XAV(W)2≍xHQHP/L2. □
There are O(κL+1) dyads for m in Bκ and O(1) for
n given m, so the balanced composites contribute at most
Cbal(κ+L−1)LXA+o(XA/L),
with Cbal depending only on δ,r0,Ψ,j′,θ and the group
geometry. The residue counts are those of the manuscript's (7.30)–(7.31): there
the congruences read mn≡1 modulo D1 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.
Fix δ, Ψ, r0 and the band and group geometry; the finite
prefix of bands used for the lower bound of XA; then j′ and θ;
and j0 covering both.
Fix κ∈(0,1/50) with Cbalκ<S/4, possible
because Cbal does not depend on κ.
Fix b1 small enough for the preliminary sieve and for the subtraction
above; set b∗=b1/3; fix j∗∗ with c2s′2−j∗∗<b∗/4; fix the
bin mesh.
Fix the Type II saving D∗ so that every replacement error, after the
dyadic sums, is o(XA/L). The Type II proof then fixes K0, D0 and,
through (P), the discrepancy exponent B.
Fix S>2B+3 in Lemma 7.3 and the prime-number-theorem accuracies, and let
x→∞.
The coefficient bound of the proxies does not depend on S, so step 5 does not
feed back into step 4. For all large real x,
After enlarging Cw to absorb the fixed bound on Ψ, each summand is
at most exp(CwL). Since XA≥cAxL−CA and
u↦2u−1 is injective, at least
(ScA/5)xL−CA−1exp(−CwL) distinct primes p=2u−1
occur. As Ψ(u/x)=0 forces x≤u≤2x, they satisfy 2x−1≤p≤4x−1,
and p+1=2u with every prime factor of u at most xδ, so
P+(p+1)=max(2,P+(u))≤xδ. This proves:
Successor count, assuming (P) and (E). For every fixed 0<δ<1/4
there are c,CA,Cw>0 such that for all sufficiently large real x
Hypothesis A+, assuming (P) and (E). Given 0<δ<1/4 and η>0, the
quantity ηL−(CA+1)logL−CwL+logc tends to infinity, so the
successor count at x=y gives at least y1−η primes p≤4y−1<5y with
P+(p+1)≤yδ, for every real y beyond a threshold depending on
δ and η. No uniformity as δ→0 and no effective threshold
is claimed, and none is needed.
The counted primes lie inside the range 2x−2<p≤5x of Li and Zhuang's
Theorem 1.4, which states this count under the assumption that the manuscript's
argument is correct.