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 A337595 #5 Sep 02 2020 19:25:48
%S A337595 1,1,7,76,1359,35620,1256470,57247765,3259660095,225795951580,
%T A337595 18644190437550,1805220546542425,202173130530484350,
%U A337595 25889773647793362425,3754040522961719322325,611181508958872398483625,110903705593861290502897375,22285223101687304853202923500,4930523789420612133816212731750
%N A337595 a(0) = 1; a(n) = (1/n) * Sum_{k=1..n} binomial(n,k)^2 * k * 5^(k-1) * a(n-k).
%F A337595 Sum_{n>=0} a(n) * x^n / (n!)^2 = exp((BesselI(0,2*sqrt(5*x)) - 1) / 5).
%F A337595 Sum_{n>=0} a(n) * x^n / (n!)^2 = exp(Sum_{n>=1} 5^(n-1) * x^n / (n!)^2).
%t A337595 a[0] = 1; a[n_] := a[n] = (1/n) Sum[Binomial[n, k]^2 k 5^(k - 1) a[n - k], {k, 1, n}]; Table[a[n], {n, 0, 18}]
%t A337595 nmax = 18; CoefficientList[Series[Exp[(BesselI[0, 2 Sqrt[5 x]] - 1)/5], {x, 0, nmax}], x] Range[0, nmax]!^2
%Y A337595 Cf. A005011, A337592, A337593, A337594, A337597.
%K A337595 nonn
%O A337595 0,3
%A A337595 _Ilya Gutkovskiy_, Sep 02 2020