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 A214669 a(n) = Sum_{k=1..n*(n+1)/2} k * A214670(n,k). 1
 1, -4, 36, -720, 29264, -2370368, 379341376, -119616350464, 74306729686272, -91021121260127232, 220137897341768508416, -1052620193410626774192128, 9963741205378506824566067200, -186912918064963001770860269879296, 6955904583765468148520677987319955456 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS PROG (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)} for(n=1, 25, print1(a(n), ", ")) CROSSREFS Cf. A214670. Sequence in context: A289545 A322782 A145565 * A126152 A009446 A134052 Adjacent sequences:  A214666 A214667 A214668 * A214670 A214671 A214672 KEYWORD sign AUTHOR Paul D. Hanna, Jul 25 2012 STATUS approved

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Last modified May 8 07:02 EDT 2021. Contains 343653 sequences. (Running on oeis4.)