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 A377326 #13 Aug 28 2025 12:10:21
%S A377326 1,1,1,4,15,96,665,6028,60907,725560,9591549,142574004,2323440119,
%T A377326 41519079616,803667844993,16797423268252,376458083887875,
%U A377326 9014414549836296,229564623594841637,6197477089425914692,176767174407208663759,5312208220728020517136,167760328500471584529321
%N A377326 E.g.f. satisfies A(x) = 1 + (exp(x*A(x)) - 1)/A(x).
%F A377326 a(n) = Sum_{k=0..floor((n+1)/2)} (n-k)!/(n-2*k+1)! * Stirling2(n,k).
%t A377326 terms=23; A[_]=1; Do[A[x_] = 1 + (Exp[x*A[x]] - 1)/A[x]+ O[x]^terms // Normal, terms]; CoefficientList[Series[A[x],{x,0,terms}],x]Range[0,terms-1]! (* _Stefano Spezia_, Aug 28 2025 *)
%o A377326 (PARI) a(n) = sum(k=0, (n+1)\2, (n-k)!/(n-2*k+1)!*stirling(n, k, 2));
%Y A377326 Cf. A052894, A367162, A367163.
%Y A377326 Cf. A367180, A377324.
%K A377326 nonn,changed
%O A377326 0,4
%A A377326 _Seiichi Manyama_, Oct 24 2024