cp's OEIS Frontend

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.

A336228 a(0) = 1; a(n) = Sum_{k=0..n-1} binomial(n,k)^2 * (n-k) * a(k).

This page as a plain text file.
%I A336228 #4 Jul 13 2020 07:53:33
%S A336228 1,1,6,75,1684,59005,2977566,204512875,18346977608,2083115635065,
%T A336228 291996210173410,49525220811387871,9996609976117991436,
%U A336228 2368117724291275331869,650613686811158069472942,205196311013650099853516115,73633144885479474283911225616
%N A336228 a(0) = 1; a(n) = Sum_{k=0..n-1} binomial(n,k)^2 * (n-k) * a(k).
%F A336228 a(n) = (n!)^2 * [x^n] 1 / (1 - sqrt(x) * BesselI(1,2*sqrt(x))).
%t A336228 a[0] = 1; a[n_] := a[n] = Sum[Binomial[n, k]^2 (n - k) a[k], {k, 0, n - 1}]; Table[a[n], {n, 0, 16}]
%t A336228 nmax = 16; CoefficientList[Series[1/(1 - Sqrt[x] BesselI[1, 2 Sqrt[x]]), {x, 0, nmax}], x] Range[0, nmax]!^2
%Y A336228 Cf. A006153, A102221.
%K A336228 nonn
%O A336228 0,3
%A A336228 _Ilya Gutkovskiy_, Jul 12 2020