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Proof of the all-sequence consecutive-span ratio bound


Use the conventions of L163. The complete supporting deductions are the canonical research pages linked below; their exact examined portions also survive in the whole-statement record. No distinct-point theorem is used to infer the repeated-point assertion.

Fix α=1/200\alpha=1/200, let rr be large and put A=αlog⁡rA=\alpha\log r. If a sequence violated the proposed limsup bound, then for some 0<C<A0<C<A, eventually Mn/mn≤1+C/rM_n/m_n\le1+C/r. The mean identity gives n(Mn−mn)≤Cn(M_n-m_n)\le C and nMn≤r+CnM_n\le r+C. For n=⌊t⌋n=\lfloor t\rfloor set at=r−nmna_t=r-nm_n and bt=tMn−rb_t=tM_n-r. These are nonnegative; all rr-spans lie in [(r−at)/t,(r+bt)/t][(r-a_t)/t,(r+b_t)/t] and

at+bt≤C+(r+C)/n<Aa_t+b_t\le C+(r+C)/n<A

at every sufficiently large real tt.

The two label injections in Lemma 2.1 and the label, terminal-count and real-lift transfers apply to this hypothesis, with every coincident term counted separately. The finite scale iteration of Proposition 3.1 therefore supplies absolute C0,C1C_0,C_1 such that, when r≥C0Ar\ge C_0A, all late integer nn, all xx and all 0≤D≤S0\le D\le S satisfy

∣Nn((x,x+D/n])−D∣≤B,S=Arlog⁡2(r/A),B=3A+C1Alog⁡(r/A).\left|N_n((x,x+D/n])-D\right|\le B,\qquad S=\frac{\sqrt{Ar}}{\log^2(r/A)},\quad B=3A+\frac{C_1A}{\log(r/A)}.

One time threshold covers the entire range of DD. Proposition 1221.1 of the extraction argument chooses a short arc avoiding the early terms and reads later terms in arrival order. For B≥1B\ge1 and S≥2S\ge2 it yields a list of length L′≥⌊S⌋−BL'\ge\lfloor S\rfloor-B in (0,1)(0,1), with repetitions allowed, whose maximum prefix star discrepancy HL′H_{L'} is at most BB. The complementary arc errors have coefficients 1−u1-u and −u-u, so this is BB, not 2B2B.

The complete four-block finite-list proof gives, for every nonempty list,

HL′≥⌊log⁡4L′⌋16≥log⁡L′16log⁡4−116.H_{L'}\ge\frac{\lfloor\log_4L'\rfloor}{16} \ge\frac{\log L'}{16\log4}-\frac1{16}.

Its range and jump argument includes repeated entries and the right jump at zero; it consumes no optimized discrepancy theorem from an unprovided source. Now B=3αlog⁡r+O(1)B=3\alpha\log r+O(1) and log⁡S=12log⁡r−32log⁡log⁡r+O(1)\log S=\frac12\log r-\frac32\log\log r+O(1). Thus L′≥S/2>0L'\ge S/2>0 for all sufficiently large rr, and the two discrepancy bounds imply

3αlog⁡r+O(1)≥log⁡r32log⁡4−O(log⁡log⁡r).3\alpha\log r+O(1)\ge \frac{\log r}{32\log4}-O(\log\log r).

This is impossible eventually, since 3/200<1/64<1/(32log⁡4)3/200<1/64<1/(32\log4). All constants in this comparison are absolute. The sequence-dependent time threshold only changes how late the extraction is made. Hence one absolute r0r_0 gives the claimed inequality for every sequence. Infinite limsup ratios satisfy it directly.

For fixed r≥r0r\ge r_0, every value in the infimum defining μr\mu_r is at least 1+log⁡r/(200r)1+\log r/(200r). Taking that infimum, then subtracting one and multiplying by rr, proves the quantitative consequence. Its lower bound log⁡r/200\log r/200 tends to infinity. No limit and extremum are interchanged.