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A307607
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a(n) = 1 + Sum_{d|n, d > 1} d^2*a(n/d).
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3
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1, 5, 10, 37, 26, 122, 50, 293, 172, 330, 122, 1306, 170, 642, 710, 2341, 290, 2876, 362, 3562, 1382, 1578, 530, 13082, 1276, 2202, 3088, 6946, 842, 12822, 962, 18725, 3398, 3762, 3750, 37756, 1370, 4698, 4742, 35818, 1682, 25014, 1850, 17098, 17072, 6882
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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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L.g.f.: -log(Product_{k>=1} (1 - x^k)^(k*A074206(k))) = Sum_{n>=1} a(n)*x^n/n.
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MATHEMATICA
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a[n_] := a[n] = 1 + DivisorSum[n, #^2 a[n/#] &, # > 1 &]; Table[a[n], {n, 1, 46}]
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PROG
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(PARI) a(n) = 1 + sumdiv(n, d, if (d>1, d^2*a(n/d))); \\ Michel Marcus, Apr 20 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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