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%I #12 Sep 08 2022 08:46:22
%S 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,
%T 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,
%U 0,0,18,0,0,0,67,0,0,8,22,0,0,0,40,6,0,0
%N a(n) = Sum_{d|n} (sigma(n) mod sigma(d)).
%H Vaclav Kotesovec, <a href="/A318952/b318952.txt">Table of n, a(n) for n = 1..10000</a>
%F a(A005117(n)) = 0.
%F a(A168363(n)) = 1.
%e For n = 4; a(4) = (7 mod 1) + (7 mod 3) + (7 mod 7) = 0 + 1 + 0 = 1.
%t Table[Sum[Mod[DivisorSigma[1, n], DivisorSigma[1, d]], {d, Divisors[n]}], {n, 1, 100}] (* _Vaclav Kotesovec_, Sep 06 2018 *)
%o (Magma) [&+[SumOfDivisors(n) mod SumOfDivisors(d): d in Divisors(n)] : n in [1..1000]]
%o (PARI) a(n) = my(sn = sigma(n)); sumdiv(n, d, sn % sigma(d)); \\ _Michel Marcus_, Sep 06 2018
%Y Cf. A000203, A005117, A168363.
%K nonn,look
%O 1,12
%A _Jaroslav Krizek_, Sep 05 2018
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