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 A160612 #13 Sep 08 2022 08:45:45
%S A160612 1,1,1,3,3,15,9,315,315,567,14175,6237,467775,6081075,773955,
%T A160612 638512875,9823275,10854718875,7514805375,21837140325,9280784638125,
%U A160612 38979295480125,2143861251406875,3792985290950625,1183411410776595,336196423516078125,9615217712559834375
%N A160612 Denominator of Laguerre(n, -4).
%H A160612 Alois P. Heinz, <a href="/A160612/b160612.txt">Table of n, a(n) for n = 0..507</a>
%p A160612 a:= n-> denom(add(binomial(n, i)*4^i/i!, i=0..n)):
%p A160612 seq(a(n), n=0..25); # _Alois P. Heinz_, Jun 27 2017
%t A160612 Denominator[Table[LaguerreL[n, -4], {n, 0, 50}]] (* _G. C. Greubel_, May 12 2018 *)
%o A160612 (PARI) for(n=0,30, print1(denominator(sum(k=0,n, binomial(n,k)*(4^k/k!))), ", ")) \\ _G. C. Greubel_, May 12 2018
%o A160612 (PARI) a(n) = denominator(pollaguerre(n, 0, -4)); \\ _Michel Marcus_, Feb 05 2021
%o A160612 (Magma) [Denominator((&+[Binomial(n,k)*(4^k/Factorial(k)): k in [0..n]])): n in [0..30]]; // _G. C. Greubel_, May 12 2018
%Y A160612 For numerators see A160611.
%Y A160612 Cf. A289147.
%K A160612 nonn,frac
%O A160612 0,4
%A A160612 _N. J. A. Sloane_, Nov 14 2009