|
%I #14 Nov 17 2019 01:42:58
%S 0,1,2,9,16,55,96,294,512,1467,2560,7018,12288,32630,57344,148620,
%T 262144,666451,1179648,2952258,5242880,12949986,23068672,56346964,
%U 100663296,243517150,436207616,1046377764,1879048192,4474004812,8053063680,19047319832,34359738368
%N a(n) = Sum_{k=0..ceiling(n/2)} k*binomial(n,k).
%H G. C. Greubel, <a href="/A185252/b185252.txt">Table of n, a(n) for n = 0..1000</a>
%F a(2*n) = A185251(2*n).
%t Table[Sum[k Binomial[n, k], {k, 0, Ceiling[n/2]}], {n, 0, 50}] (* _G. C. Greubel_, Jun 25 2017 *)
%o (PARI) a(n)=sum(k=0,(n+1)\2,k*binomial(n,k))
%K nonn,easy
%O 0,3
%A _M. F. Hasler_, Jan 24 2012
|
