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A367864
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a(n) = Sum_{d|n} d * binomial(n,d).
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0
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1, 4, 6, 20, 10, 102, 14, 352, 270, 1370, 22, 8340, 26, 24234, 16410, 110512, 34, 551754, 38, 1944880, 817992, 7760258, 46, 39190392, 265700, 135208502, 42190254, 570003392, 58, 2631501240, 62, 9701577536, 2128920354, 39671306930, 48694870, 179231802444, 74
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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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a(p) = 2p, for p prime.
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MAPLE
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a:= n-> n*add(binomial(n-1, d-1), d=numtheory[divisors](n)):
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MATHEMATICA
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Table[Sum[d*Binomial[n, d], {d, Divisors[n]}], {n, 50}]
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PROG
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(PARI) a(n) = sumdiv(n, d, d * binomial(n, d)); \\ Michel Marcus, Dec 03 2023
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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