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A363566
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G.f. satisfies A(x) = exp( Sum_{k>=1} (3 * (-1)^k + A(x^k)) * x^k/k ).
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2
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1, -2, 2, 0, -2, 0, 5, -3, -9, 11, 16, -34, -27, 102, 30, -296, 56, 807, -548, -2056, 2572, 4770, -9846, -9351, 33822, 11496, -107296, 17853, 316498, -210013, -862785, 1069352, 2122294, -4347217, -4402138, 15657617, 5883290, -51677928, 7420844, 157867636
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OFFSET
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0,2
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LINKS
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FORMULA
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A(x) = B(x)/(1 + x)^3 where B(x) is the g.f. of A363575.
A(x) = Sum_{k>=0} a(k) * x^k = 1/(1+x)^3 * 1/Product_{k>=0} (1-x^(k+1))^a(k).
a(0) = 1; a(n) = (1/n) * Sum_{k=1..n} ( 3 * (-1)^k + Sum_{d|k} d * a(d-1) ) * a(n-k).
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PROG
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(PARI) seq(n) = my(A=1); for(i=1, n, A=exp(sum(k=1, i, (3*(-1)^k+subst(A, x, x^k))*x^k/k)+x*O(x^n))); Vec(A);
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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