A160615 Numerator of Laguerre(n, -2).

1, 3, 7, 43, 27, 719, 3661, 13991, 66769, 133261, 2363513, 116441047, 513267739, 153434147, 96790969339, 2053217625931, 136839921293, 67725860135459, 837687671342383, 7232743280136193, 2996031500521181, 4142815387557270467

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..494

Formula

Numerators of coefficients in expansion of exp(2*x/(1 - x))/(1 - x). - Ilya Gutkovskiy, Aug 29 2018

Example

1, 3, 7, 43/3, 27, 719/15, 3661/45, 13991/105, 66769/315, 133261/405, 2363513/4725, 116441047/155925, ...

Mathematica

Numerator[Table[LaguerreL[n, -2], {n, 0, 50}]] (* G. C. Greubel, May 06 2018 *)

Prog

(PARI) for(n=0, 30, print1(numerator(sum(k=0, n, binomial(n, k)*(2^k/k!))), ", ")) \\ G. C. Greubel, May 06 2018
(Magma) [Numerator((&+[Binomial(n, k)*(2^k/Factorial(k)): k in [0..n]])): n in [0..30]]; // G. C. Greubel, May 06 2018

Crossrefs

For denominators see A160616.

Cf. A087912.

Sequence in context: A019018 A018993 A217759 * A106965 A337829 A257366

Adjacent sequences: A160612 A160613 A160614 * A160616 A160617 A160618

Keyword

nonn,frac

Author

N. J. A. Sloane, Nov 14 2009

Status

approved