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

Author

Daniel Suteu, Dec 03 2016

Keywords

• nonn
• easy

Links

• Daniel Suteu, Table of n, a(n) for n = 0..19
• Wikipedia, Sophomore's dream.

Crossrefs

Cf. A073009.

Programs

PARI

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

Formula

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

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