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