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Kaneko, Suzuki and Tachiya, arXiv:2601.20743v1, Theorem 2, printed/PDF p. 3.

Use q,d,h,Nc,Scq,d,\mathrm h,\mathcal N_c,S_c and condition (G) from Theorem 1. Let a,ba,b be sequences of algebraic integers of Q(q)\mathbb Q(q), with a(n)≥0a(n)\ge0 for every n≥1n\ge1 and Na\mathcal N_a infinite.

Theorem. Assume

ρ=lim sup⁡n→∞max⁡{h(a(n)),h(b(n))}1/n<q.\rho=\limsup_{n\to\infty} \max\{\mathrm h(a(n)),\mathrm h(b(n))\}^{1/n}<q.

Suppose real sequences xj,yj,zj≥1x_j,y_j,z_j\ge1 satisfy

xj→∞,Sa(xj),Sb(xj)=O(yj),#Na(xj),#Nb(xj)=o(xj/zj),x_j\to\infty,\qquad S_a(x_j),S_b(x_j)=O(y_j),\qquad \#\mathcal N_a(x_j),\#\mathcal N_b(x_j)=o(x_j/z_j), lim sup⁡j→∞yj(d−1)/xj<q/ρ,\limsup_{j\to\infty}y_j^{(d-1)/x_j}<q/\rho,

and

∑1≤m<xja(m),∑1≤m<xj∣b(m)∣=o(qzjxj/yjd−1).\sum_{1\le m<x_j}a(m),\quad \sum_{1\le m<x_j}|b(m)| =o(q^{z_j}x_j/y_j^{d-1}).

The last two sums use the distinguished real embedding, whereas ScS_c uses the maximum over conjugates. If Nb\mathcal N_b is infinite, also assume (G). Then

∑n≥1a(n)+b(n)qn∉Q(q).\sum_{n\ge1}\frac{a(n)+b(n)}{q^n}\notin\mathbb Q(q).

The root bound gives convergence. In this setting ρ≥1\rho\ge1 because a nonzero algebraic integer has conjugate size at least one and Na\mathcal N_a is infinite, so q/ρq/\rho is well defined.

Proof pointer and standing

The proof is on pp. 12–13, using Lemma 4 on pp. 11–12. That lemma separates coefficients below the cutoff from the entire remainder beyond it. The root and auxiliary growth bounds control the latter; the mass estimate controls the former. Together they supply Theorem 1's averaged complete-tail condition for a suitable fixed η\eta.

This is a checked author statement extraction with a read proof route, not a complete reconstructed proof or an independent review. For integer bases, d=1d=1 removes the auxiliary yjy_j factors and yields Theorem 3.

Bears on. Problem 249 through possible sparse transformations. No admissible transformation of its full series has been constructed here.