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A160622

Denominator of Laguerre(n, 1).

1, 1, 2, 3, 8, 15, 144, 420, 5760, 4536, 403200, 1995840, 6220800, 259459200, 1341204480, 46702656000, 1394852659200, 11115232128000, 376610217984000, 96543730483200, 128047474114560000, 1277273554292736000

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..450

FORMULA

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

EXAMPLE

1, 0, -1/2, -2/3, -5/8, -7/15, -37/144, -17/420, 887/5760, 1405/4536, 168919/403200, 958271/1995840, ... = A160621/A160622.

MATHEMATICA

Denominator[Table[LaguerreL[n, 1], {n, 0, 50}]] (* G. C. Greubel, May 06 2018 *)

PROG

(PARI) for(n=0, 30, print1(denominator(sum(k=0, n, binomial(n, k)*((-1)^k/k!))), ", ")) \\ G. C. Greubel, May 06 2018

(Magma) [Denominator((&+[Binomial(n, k)*((-1)^k/Factorial(k)): k in [0..n]])): n in [0..30]]; // G. C. Greubel, May 06 2018

CROSSREFS

For numerators see A160621.

Cf. A009940.

Sequence in context: A129108 A230284 A264235 * A153699 A182670 A234696

Adjacent sequences: A160619 A160620 A160621 * A160623 A160624 A160625

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane, Nov 14 2009

STATUS

approved

URL: https://oeis.org/A160622

⇱ A160622 - OEIS