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 A343710 #8 Oct 20 2021 07:49:21 %S A343710 1,5,45,609,11009,248837,6749629,213596401,7725031521,314310704101, %T A343710 14209394894765,706617979262049,38333841625642785,2252901018519028901, %U A343710 142589176837851349757,9669282207517755852721,699408060608904410296897,53752166013267632536864581,4374061543586452325644329133 %N A343710 a(n) = 1 + 4 * Sum_{k=0..n-1} binomial(n,k) * (n-k-1)! * a(k). %H A343710 Seiichi Manyama, <a href="/A343710/b343710.txt">Table of n, a(n) for n = 0..359</a> %F A343710 E.g.f.: exp(x) / (1 + 4 * log(1 - x)). %t A343710 a[n_] := a[n] = 1 + 4 Sum[Binomial[n, k] (n - k - 1)! a[k], {k, 0, n - 1}]; Table[a[n], {n, 0, 18}] %t A343710 nmax = 18; CoefficientList[Series[Exp[x]/(1 + 4 Log[1 - x]), {x, 0, nmax}], x] Range[0, nmax]! %o A343710 (PARI) N=20; x='x+O('x^N); Vec(serlaplace(exp(x)/(1+4*log(1-x)))) \\ _Seiichi Manyama_, Oct 20 2021 %Y A343710 Cf. A201365, A291979, A343707, A343709. %K A343710 nonn %O A343710 0,2 %A A343710 _Ilya Gutkovskiy_, Apr 26 2021