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A362683
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Expansion of Sum_{k>0} (1/(1 - k*x^k)^2 - 1).
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6
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2, 7, 10, 25, 16, 78, 22, 153, 136, 298, 34, 1254, 40, 1214, 2004, 3825, 52, 11385, 58, 20894, 18932, 25006, 70, 150002, 18826, 115274, 199828, 389510, 88, 1334624, 94, 1725281, 2131188, 2360266, 725948, 14878299, 112, 10486958, 22329428, 37317986, 124, 120957336, 130
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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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If p is prime, a(p) = 1 + 3*p.
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MATHEMATICA
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a[n_] := DivisorSum[n, (n/#)^# * (# + 1) &]; Array[a, 50] (* Amiram Eldar, Jul 17 2023 *)
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PROG
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(PARI) a(n) = sumdiv(n, d, (n/d)^d*(d+1));
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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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