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A364093 Sum of divisors of 5*n-2 of form 5*k+1.

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%I A364093 #15 Jul 17 2023 00:58:22
%S A364093 1,1,1,7,1,1,12,1,1,23,1,1,22,1,1,33,1,12,32,1,1,43,1,1,42,17,1,53,12,
%T A364093 1,52,1,1,84,1,1,62,1,1,84,1,43,72,1,1,83,1,1,82,32,12,93,1,1,113,1,1,
%U A364093 155,1,1,102,12,1,113,1,42,112,27,1,123,1,1,133,63,1,154,1,1,132,1,32,194,1,12,142
%N A364093 Sum of divisors of 5*n-2 of form 5*k+1.
%F A364093 a(n) = A284097(5*n-2).
%F A364093 G.f.: Sum_{k>0} (5*k-4) * x^(3*k-2) / (1 - x^(5*k-4)).
%t A364093 a[n_] := DivisorSum[5*n - 2, # &, Mod[#, 5] == 1 &]; Array[a, 100] (* _Amiram Eldar_, Jul 17 2023 *)
%o A364093 (PARI) a(n) = sumdiv(5*n-2, d, (d%5==1)*d);
%Y A364093 Cf. A364092, A364094, A364095.
%Y A364093 Cf. A284097, A359236, A364097.
%K A364093 nonn
%O A364093 1,4
%A A364093 _Seiichi Manyama_, Jul 04 2023