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 A160615 #13 Sep 08 2022 08:45:45
%S A160615 1,3,7,43,27,719,3661,13991,66769,133261,2363513,116441047,513267739,
%T A160615 153434147,96790969339,2053217625931,136839921293,67725860135459,
%U A160615 837687671342383,7232743280136193,2996031500521181,4142815387557270467
%N A160615 Numerator of Laguerre(n, -2).
%H A160615 G. C. Greubel, <a href="/A160615/b160615.txt">Table of n, a(n) for n = 0..494</a>
%F A160615 Numerators of coefficients in expansion of exp(2*x/(1 - x))/(1 - x). - _Ilya Gutkovskiy_, Aug 29 2018
%e A160615 1, 3, 7, 43/3, 27, 719/15, 3661/45, 13991/105, 66769/315, 133261/405, 2363513/4725, 116441047/155925, ...
%t A160615 Numerator[Table[LaguerreL[n, -2], {n, 0, 50}]] (* _G. C. Greubel_, May 06 2018 *)
%o A160615 (PARI) for(n=0,30, print1(numerator(sum(k=0,n, binomial(n,k)*(2^k/k!))), ", ")) \\ _G. C. Greubel_, May 06 2018
%o A160615 (Magma) [Numerator((&+[Binomial(n,k)*(2^k/Factorial(k)): k in [0..n]])): n in [0..30]]; // _G. C. Greubel_, May 06 2018
%Y A160615 For denominators see A160616.
%Y A160615 Cf. A087912.
%K A160615 nonn,frac
%O A160615 0,2
%A A160615 _N. J. A. Sloane_, Nov 14 2009