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 A380491 #13 Jan 25 2025 11:27:13
%S A380491 1,0,3,34,501,9276,207775,5470158,165625929,5671386136,216730118331,
%T A380491 9144481575450,422249317829053,21180324426577044,1146880568461500951,
%U A380491 66677192513929212166,4142571510546929867025,273910161452560881843888,19204878684852222745880179
%N A380491 a(n) = n! * Sum_{k=0..n} binomial(2*n-3,k)/(n-k)!.
%H A380491 Wikipedia, <a href="https://en.wikipedia.org/wiki/Laguerre_polynomials">Laguerre polynomials</a>
%H A380491 <a href="/index/La#Laguerre">Index entries for sequences related to Laguerre polynomials</a>
%F A380491 a(n) = n! * LaguerreL(n, n-3, -1).
%F A380491 a(n) = n! * [x^n] exp(x/(1 - x))/(1 - x)^(n-2).
%o A380491 (PARI) a(n) = n!*pollaguerre(n, n-3, -1);
%Y A380491 Cf. A082545, A152059, A251568, A293985, A343832, A380492, A380493.
%K A380491 nonn
%O A380491 0,3
%A A380491 _Seiichi Manyama_, Jan 25 2025