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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.

A364098 Expansion of Sum_{k>0} k * x^(2*k-1) / (1 - x^(5*k-4)).

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%I A364098 #12 Jul 12 2023 01:01:09
%S A364098 1,1,3,1,4,1,5,1,8,1,7,1,8,1,11,4,10,1,11,1,14,1,17,1,14,1,20,1,16,6,
%T A364098 17,1,20,1,19,1,26,4,27,1,22,1,23,8,26,1,25,1,29,1,42,1,28,1,33,1,32,
%U A364098 10,31,4,32,1,41,1,44,1,35,1,38,1,44,17,38,1,48,1,40,1,53,1,44,4,43,1,44,14,59,1
%N A364098 Expansion of Sum_{k>0} k * x^(2*k-1) / (1 - x^(5*k-4)).
%F A364098 a(n) = (1/5) * Sum_{d | 5*n-3, d==1 (mod 5)} (d+4).
%F A364098 G.f.: Sum_{k>0} x^k / (1 - x^(5*k-3))^2.
%t A364098 a[n_] := DivisorSum[5*n - 3, # + 4 &, Mod[#, 5] == 1 &]/5; Array[a, 100] (* _Amiram Eldar_, Jul 12 2023 *)
%o A364098 (PARI) a(n) = sumdiv(5*n-3, d, (d%5==1)*(d+4))/5;
%Y A364098 Cf. A359237, A364094.
%K A364098 nonn
%O A364098 1,3
%A A364098 _Seiichi Manyama_, Jul 04 2023