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A309955
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a(n) = [x^n] (1 + p(x))^n, where p(x) is the g.f. of A000040.
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3
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1, 2, 10, 59, 362, 2287, 14707, 95762, 629386, 4166627, 27743445, 185602188, 1246543559, 8399791922, 56762121398, 384513835219, 2610322687850, 17753944125159, 120954505004605, 825274753259894, 5638438272353597, 38569743775323134, 264127692090124488
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OFFSET
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0,2
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LINKS
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MAPLE
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b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i=1, ithprime(n),
(h-> add(b(j, h)*b(n-j, i-h), j=0..n))(iquo(i, 2))))
end:
a:= n-> b(n$2):
seq(a(n), n=0..31);
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MATHEMATICA
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b[n_, i_] := b[n, i] = If[n == 0, 1, If[i == 1, Prime[n],
Function[h, Sum[b[j, h]*b[n-j, i-h], {j, 0, n}]][Quotient[i, 2]]]];
a[n_] := b[n, n];
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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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