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 A160602 #12 Sep 08 2022 08:45:45
%S A160602 1,1,2,1,8,20,16,280,4480,64,44800,49280,1971200,1830400,14350336,
%T A160602 896896000,74547200,243955712000,6823936000,109062553600,
%U A160602 52973240320000,51913775513600,3359126650880000,93815608606720000,2101469632790528000
%N A160602 Denominator of Laguerre(n, -9).
%H A160602 G. C. Greubel, <a href="/A160602/b160602.txt">Table of n, a(n) for n = 0..492</a>
%t A160602 Denominator[Table[LaguerreL[n, -9], {n, 0, 50}]] (* _G. C. Greubel_, May 13 2018 *)
%o A160602 (PARI) for(n=0,30, print1(denominator(sum(k=0,n, binomial(n,k)*(9^k/k!))), ", ")) \\ _G. C. Greubel_, May 13 2018
%o A160602 (PARI) a(n) = denominator(pollaguerre(n, 0, -9)); \\ _Michel Marcus_, Feb 05 2021
%o A160602 (Magma) [Denominator((&+[Binomial(n,k)*(9^k/Factorial(k)): k in [0..n]])): n in [0..30]]; // _G. C. Greubel_, May 13 2018
%Y A160602 For numerators see A160601.
%Y A160602 Cf. A289215.
%K A160602 nonn,frac
%O A160602 0,3
%A A160602 _N. J. A. Sloane_, Nov 14 2009