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 A318952 a(n) = Sum_{d|n} (sigma(n) mod sigma(d)). 1
 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 5, 0, 0, 0, 5, 0, 6, 0, 6, 0, 0, 0, 8, 1, 0, 1, 10, 0, 0, 0, 4, 0, 0, 0, 31, 0, 0, 0, 12, 0, 0, 0, 12, 8, 0, 0, 30, 1, 6, 0, 16, 0, 6, 0, 9, 0, 0, 0, 30, 0, 0, 8, 13, 0, 0, 0, 18, 0, 0, 0, 67, 0, 0, 8, 22, 0, 0, 0, 40, 6, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,12 LINKS Vaclav Kotesovec, Table of n, a(n) for n = 1..10000 FORMULA a(A005117(n)) = 0. a(A168363(n)) = 1. EXAMPLE For n = 4; a(4) = (7 mod 1) + (7 mod 3) + (7 mod 7) = 0 + 1 + 0 = 1. MATHEMATICA Table[Sum[Mod[DivisorSigma[1, n], DivisorSigma[1, d]], {d, Divisors[n]}], {n, 1, 100}] (* Vaclav Kotesovec, Sep 06 2018 *) PROG (MAGMA) [&+[SumOfDivisors(n) mod SumOfDivisors(d): d in Divisors(n)] : n in [1..1000]] (PARI) a(n) = my(sn = sigma(n)); sumdiv(n, d, sn % sigma(d)); \\ Michel Marcus, Sep 06 2018 CROSSREFS Cf. A000203, A005117, A168363. Sequence in context: A036297 A087935 A243829 * A089877 A278715 A079074 Adjacent sequences:  A318949 A318950 A318951 * A318953 A318954 A318955 KEYWORD nonn,look AUTHOR Jaroslav Krizek, Sep 05 2018 STATUS approved

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Last modified March 21 04:59 EDT 2019. Contains 321364 sequences. (Running on oeis4.)