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%I #11 Jun 26 2023 06:33:16
%S 0,1,0,0,2,0,0,2,0,0,2,0,0,2,1,0,2,0,0,2,0,0,2,0,2,2,0,0,2,0,0,2,0,0,
%T 4,0,0,2,0,0,2,1,0,2,2,0,2,0,0,2,0,0,2,0,2,2,0,0,4,0,0,2,0,0,4,0,0,2,
%U 0,0,2,0,0,2,2,2,2,0,0,2,0,0,3,0,2,2,0,0,2,0,0,2,2,0,4,0,0,2,0,0
%N Number of divisors of 7*n-5 of form 7*k+3.
%F a(n) = A363805(7*n-5).
%F G.f.: Sum_{k>0} x^(3*k-1)/(1 - x^(7*k-4)).
%t a[n_] := DivisorSum[7*n - 5, 1 &, Mod[#, 7] == 3 &]; Array[a, 100] (* _Amiram Eldar_, Jun 26 2023 *)
%o (PARI) a(n) = sumdiv(7*n-5, d, d%7==3);
%Y Cf. A363852, A363857, A363888.
%Y Cf. A363805.
%K nonn
%O 1,5
%A _Seiichi Manyama_, Jun 26 2023
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