This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A364103 #15 Jul 17 2023 00:59:47
%S A364103 0,0,0,4,0,0,0,13,0,0,0,18,0,0,0,23,9,0,0,28,0,0,0,33,0,23,0,38,0,0,0,
%T A364103 43,0,0,28,48,0,0,0,67,0,0,0,91,0,0,0,63,0,0,0,68,38,33,0,73,0,0,0,78,
%U A364103 0,43,0,83,0,0,0,126,0,0,48,93,19,0,0,98,0,0,0,156,0,43,0,108,0,0,0,113,58
%N A364103 Sum of divisors of 5*n-4 of form 5*k+4.
%F A364103 a(n) = A284103(5*n-4).
%F A364103 G.f.: Sum_{k>0} (5*k-1) * x^(4*k) / (1 - x^(5*k-1)).
%t A364103 a[n_] := DivisorSum[5*n - 4, # &, Mod[#, 5] == 4 &]; Array[a, 100] (* _Amiram Eldar_, Jul 17 2023 *)
%o A364103 (PARI) a(n) = sumdiv(5*n-4, d, (d%5==4)*d);
%Y A364103 Cf. A364100, A364101, A364102.
%Y A364103 Cf. A284103, A359241, A364107.
%K A364103 nonn
%O A364103 1,4
%A A364103 _Seiichi Manyama_, Jul 04 2023