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A297842
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a(n) = Sum_{d|n} max(d, n/d)^3.
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4
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1, 16, 54, 136, 250, 486, 686, 1152, 1485, 2250, 2662, 4016, 4394, 6174, 7000, 9280, 9826, 13554, 13718, 18250, 19208, 23958, 24334, 32560, 31375, 39546, 40824, 50078, 48778, 63182, 59582, 74752, 74536, 88434, 86436, 110106, 101306, 123462, 123032, 147024
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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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MATHEMATICA
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f[n_] := Block[{d = Divisors@ n}, Plus @@ (Max[#, n/#]^3 & /@ d)]; Array[f, 40] (* Robert G. Wilson v, Jan 07 2018 *)
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PROG
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(PARI) {a(n) = sumdiv(n, d, max(d, n/d)^3)}
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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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