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A192733
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Euler transform is sequence A004016.
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1
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6, -21, 76, -345, 1734, -8906, 46662, -250257, 1365388, -7538421, 42030150, -236312690, 1338000774, -7620721077, 43626920908, -250869973089, 1448248263558, -8389624496618, 48751103123142, -284073748405401, 1659452645344972, -9715933503018165
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OFFSET
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1,1
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LINKS
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FORMULA
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a(q) = Prod_{k>0} (1 - q^k)^-a(k).
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PROG
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(PARI) {a(n) = local(A, S); if( n<1, 0, A = 1 + x * O(x^n); S = sum( k= 1, n, 6 * sumdiv( k, d, kronecker( d, 3)) * x^k, A); for( k = 1, n-1, S *= (A - x^k) ^ polcoeff( S, k)); polcoeff( S, n))}
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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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