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Statement

Theorem 3 (Rautenbach and Stella [5]; p. 3). "Let M(k)M(k) be the maximum number of cycles in a Hamiltonian graph with kk chords."

M(k)≤2k+1−1−k(k−2log⁡2(k)+2−14log⁡2(k))M(k)\le 2^{k+1}-1-k\left(\frac{\sqrt k-2}{\log_2(k)+2}-\frac14\log_2(k)\right)

The paper then concludes (p. 3) that m(n)m(n) is at least n+Cn+C, where CC is the largest integer kk such that "the expression in Theorem 1 [sic]" is less than n−2n-2. The expression meant is the right-hand side of Theorem 3, since the paper's Theorem 1 (p. 1) is Bondy's sufficient condition for pancyclicity and contains no such expression.

The theorem is the paper's quotation of an outside result; the paper's [5] is D. Rautenbach and I. Stella, On the maximum number of cycles in a Hamiltonian graph, Discrete Math. 304 (2005), 101--107.

Source. S. Griffin, Minimal pancyclicity, arXiv:1312.0274v1 (1 December 2013; 6 pages), the only arXiv version; Theorem 3 and the conclusion after it on p. 3. A preprint. The edition read is identified in the source digest.

Read depth. Claims checked: the statement and the sentence after it were read on the page image of p. 3. The Rautenbach--Stella paper is not held, so the quoted bound was not checked against it.

Proof pointer

No proof of the bound is in the paper. The conclusion follows as in Claim 1: a pancyclic graph with kk chords has at least n−2n-2 cycles, so M(k)≥n−2M(k)\ge n-2. The paper's wording "the largest integer kk" is as printed.

Dependencies

Rautenbach and Stella 2005 (the paper's [5]; not held).

Bears on

  • Problem 1016: a lower bound on h(n)=m(n)−nh(n)=m(n)-n in implicit form; the correction to 2k+1−12^{k+1}-1 is of lower order than 2k+12^{k+1}, so the bound keeps the form log⁡2n+O(1)\log_2n+O(1) and does not reach the log⁡∗n\log_*n term the problem asks about.