A062807 a(n) = Sum_{i=1..n} i*(n-i)^i.

0, 1, 4, 14, 50, 187, 738, 3084, 13652, 63917, 315736, 1641314, 8956110, 51175799, 305527878, 1901829488, 12319405728, 82896050937, 578485474092, 4180313933206, 31237475311690, 241063266361235, 1918899090047882

Offset

1,3

Links

Harry J. Smith, Table of n, a(n) for n = 1..200

Formula

G.f.: x*Sum_{k>=1} k*x^k/(1 - k*x)^2. - Ilya Gutkovskiy, Oct 11 2018

Mathematica

Table[Sum[i (n-i)^i, {i, n}], {n, 30}] (* Harvey P. Dale, Dec 25 2017 *)

Prog

(PARI) a(n)={sum(i=1, n, i*(n - i)^i)} \\ Harry J. Smith, Aug 11 2009

Crossrefs

Cf. A101495.

Sequence in context: A051924 A272687 A076024 * A363507 A117421 A034743

Adjacent sequences: A062804 A062805 A062806 * A062808 A062809 A062810

Keyword

nonn,easy

Author

Olivier Gérard, Jun 23 2001

Extensions

Prior Mathematica program replaced by Harvey P. Dale, Dec 25 2017

Status

approved