A015557 a(n) = ceiling((n/e)^n).

1, 1, 1, 2, 5, 22, 116, 751, 5629, 47812, 454000, 4765191, 54782415, 684597511, 9239952803, 133952757202, 2075907567337, 34247231626810, 599244998013964, 11084682598687313, 216127622080213322

Offset

0,4

Links

Iain Fox, Table of n, a(n) for n = 0..450 (terms 0..200 from Vincenzo Librandi)

Maple

Digits := 64: E:=exp(1); f := n->ceil(evalf((n/E)^n));

Mathematica

Join[{1}, Table[Ceiling[(n/E)^n], {n, 20}]] (* Harvey P. Dale, Aug 09 2014 *)

Prog

(Magma) [Ceiling((n/Exp(1))^n): n in [0..20]]; // Vincenzo Librandi, Aug 10 2014
(PARI) for(n=0, 20, print1(ceil((n^n*exp(-n))), ", ")) \\ G. C. Greubel, Dec 30 2017

Crossrefs

Sequence in context: A215096 A115602 A115601 * A066305 A020093 A329260

Adjacent sequences: A015554 A015555 A015556 * A015558 A015559 A015560

Keyword

nonn

Author

N. J. A. Sloane

Extensions

Typo in Mathematica program fixed by Vincenzo Librandi, Aug 10 2014

Status

approved