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A062807
a(n) = Sum_{i=1..n} i*(n-i)^i.
2
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
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
KEYWORD
nonn,easy
AUTHOR
Olivier Gérard, Jun 23 2001
EXTENSIONS
Prior Mathematica program replaced by Harvey P. Dale, Dec 25 2017
STATUS
approved