A062807 - OEIS

%I #17 Oct 11 2018 14:09:05

%S 0,1,4,14,50,187,738,3084,13652,63917,315736,1641314,8956110,51175799,

%T 305527878,1901829488,12319405728,82896050937,578485474092,

%U 4180313933206,31237475311690,241063266361235,1918899090047882

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

%H Harry J. Smith, <a href="/A062807/b062807.txt">Table of n, a(n) for n = 1..200</a>

%F G.f.: x*Sum_{k>=1} k*x^k/(1 - k*x)^2. - _Ilya Gutkovskiy_, Oct 11 2018

%t Table[Sum[i (n-i)^i,{i,n}],{n,30}] (* _Harvey P. Dale_, Dec 25 2017 *)

%o (PARI) a(n)={sum(i=1, n, i*(n - i)^i)} \\ _Harry J. Smith_, Aug 11 2009

%Y Cf. A101495.

%K nonn,easy

%O 1,3

%A _Olivier Gérard_, Jun 23 2001

%E Prior Mathematica program replaced by _Harvey P. Dale_, Dec 25 2017