%I #3 Jul 25 2012 12:46:43
%S 1,-4,36,-720,29264,-2370368,379341376,-119616350464,74306729686272,
%T -91021121260127232,220137897341768508416,-1052620193410626774192128,
%U 9963741205378506824566067200,-186912918064963001770860269879296,6955904583765468148520677987319955456
%N a(n) = Sum_{k=1..n*(n+1)/2} k * A214670(n,k).
%o (PARI) {a(n)=local(A214670=x*y); A214670=sum(m=1, n, -x^m*prod(j=1, m, (1-(1+y)^j)/(1-x*(1+y)^j))+x*O(x^n)); polcoeff(subst(deriv(A214670,y),y,1), n, x)}
%o for(n=1, 25, print1(a(n),", "))
%Y Cf. A214670.
%K sign
%O 1,2
%A _Paul D. Hanna_, Jul 25 2012
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