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%I #12 Sep 08 2022 08:46:24
%S 1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,29,1,7,1,1,1,1,
%T 1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,29,1,1,1,7,1,1,1,1,1,7,1,1,
%U 1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,35,1,1
%N a(n) is the sum of divisors d of n such that d divides sigma(d).
%H Antti Karttunen, <a href="/A325470/b325470.txt">Table of n, a(n) for n = 1..20000</a>
%F a(A097603(n)) > 1.
%e For n = 12, divisors d of 12: 1, 2, 3, 4, 6, 12; corresponding sigma(d): 1, 3, 4, 7, 12, 28; d divides sigma(d) for 2 divisors d: 1 and 6; a(12) = 1 + 6 = 7.
%t a[n_] := DivisorSum[n, # &, Divisible[DivisorSigma[1, #], #] &]; Array[a, 100] (* _Amiram Eldar_, Aug 17 2019 *)
%o (Magma) [&+[d: d in Divisors(n) | IsIntegral(SumOfDivisors(d) / d)] : n in [1..100]]
%o (PARI) a(n)={sumdiv(n, d, if(sigma(d) % d == 0, d))} \\ _Andrew Howroyd_, Aug 16 2019
%Y Cf. A000203, A097603, A325469, A325471.
%K nonn
%O 1,6
%A _Jaroslav Krizek_, Aug 16 2019
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