A279017 a(n) = unreduced numerator in Sum_{k=1..n}(1/k^k).

0, 1, 5, 139, 35692, 111565148, 5205269945088, 4286767657466006784, 71920030250887607243833344, 27863293344390107424172413346185216, 278632933465479015464665989671020186828800000, 79497227734495207011816776516244120065118266248396800000

Offset

0,3

Links

Daniel Suteu, Table of n, a(n) for n = 0..19

Wikipedia, Sophomore's dream.

Formula

a(n) ~ A073009 * A002109(n).

a(0) = 0, a(n) = n^n * a(n-1) + A002109(n-1).

Prog

(PARI) sum(k=1, n, 1/k^k) * prod(k=1, n, k^k)

Crossrefs

Cf. A073009.

Sequence in context: A188451 A362993 A061463 * A091058 A155177 A054323

Adjacent sequences: A279014 A279015 A279016 * A279018 A279019 A279020

Keyword

nonn,easy

Author

Daniel Suteu, Dec 03 2016

Status

approved