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%I #20 Oct 07 2015 03:59:34
%S 0,2,8,24,56,120,252,476,880,1584,2740,4620,7680,12428,19824,31170,
%T 48224,73678,111384,166364,246120,360822,524216,755504,1080912,
%U 1535050,2165592,3036096,4230632,5861828,8078820,11076362,15112384,20523492,27747128
%N Sum of parts in all partitions of 2n that do not contain 1 as a part.
%C Essentially this is a bisection (even indices) of A138880.
%H Alois P. Heinz, <a href="/A182736/b182736.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = 2*n*A182746(n). - _Omar E. Pol_, Dec 05 2010
%p b:= proc(n,i) option remember; local p,q;
%p if n<0 then [0,0]
%p elif n=0 then [1,0]
%p elif i<2 then [0,0]
%p else p, q:= b(n,i-1), b(n-i,i);
%p [p[1]+q[1], p[2]+q[2]+q[1]*i]
%p fi
%p end:
%p a:= n-> b(2*n,2*n)[2]:
%p seq(a(n), n=0..34); # _Alois P. Heinz_, Dec 03 2010
%t b[n_] := (PartitionsP[n] - PartitionsP[n-1])*n; a[n_] := b[2n]; Table[a[n], {n, 0, 34}] (* _Jean-François Alcover_, Oct 07 2015 *)
%Y Cf. A135010, A138121, A138880, A182734, A182742.
%K nonn
%O 0,2
%A _Omar E. Pol_, Dec 03 2010
%E More terms from _Alois P. Heinz_, Dec 03 2010
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