This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A260952 #9 Mar 07 2022 06:14:26 %S A260952 1,-1,-1,-5,-35,-319,-3557,-46617,-699547,-11801263,-220778973, %T A260952 -4532376577,-101246459811,-2444155497191,-63397685488165, %U A260952 -1758278168174137,-51920205021872395,-1626358286062507551,-53865503179448478605,-1880864793407486366353 %N A260952 Coefficients in asymptotic expansion of the sequences A109253 and A112225. %C A260952 The values 1,5,35,319,... also are the number of Feynman diagrams of the Green's function of 2,4,6,8,... vertices which have no tadpoles (i.e. no edges that connect a vertex to itself), a subset of the graphs in A000698, vixra:1901.0148. This is likely a random coincidence. - _R. J. Mathar_, Mar 07 2022 %H A260952 Vaclav Kotesovec, <a href="/A260952/b260952.txt">Table of n, a(n) for n = 0..124</a> %F A260952 A109253(n)/(n!*2^n) ~ Sum_{k>=0} a(k)/(2*n)^k. %F A260952 A112225(n)/(n!*2^(n-1)) ~ Sum_{k>=0} a(k)/(2*n)^k. %F A260952 Conjecture: a(k) ~ -k! * 2^(k+1) / (9 * (log(3))^(k+1)). %e A260952 A109253(n)/(n!*2^n) ~ (1 - 1/(2*n) - 1/(4*n^2) - 5/(8*n^3) - 35/(16*n^4) - ... %e A260952 A112225(n)/(n!*2^(n-1)) ~ (1 - 1/(2*n) - 1/(4*n^2) - 5/(8*n^3) - 35/(16*n^4) - ... %Y A260952 Cf. A109253, A112225. %K A260952 sign %O A260952 0,4 %A A260952 _Vaclav Kotesovec_, Aug 05 2015