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A050368
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Number of ways to factor n into distinct factors with 2 kinds of 2, 3 kinds of 3, ...
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21
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1, 2, 3, 5, 5, 12, 7, 16, 12, 20, 11, 39, 13, 28, 30, 42, 17, 60, 19, 65, 42, 44, 23, 126, 35, 52, 55, 91, 29, 150, 31, 116, 66, 68, 70, 219, 37, 76, 78, 210, 41, 210, 43, 143, 150, 92, 47, 378, 70, 170, 102, 169, 53, 290, 110, 294, 114, 116, 59, 570, 61, 124, 210
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OFFSET
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1,2
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LINKS
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FORMULA
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Dirichlet g.f.: Product_{n>=2}((1+1/n^s)^n).
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PROG
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(PARI) seq(n)={my(v=vector(n, k, k==1)); for(k=2, n, my(m=logint(n, k), p=(1 + x + O(x*x^m))^k, w=vector(n)); for(i=0, m, w[k^i]=polcoef(p, i)); v=dirmul(v, w)); v} \\ Andrew Howroyd, Oct 27 2019
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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