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 A363860 #10 Jun 25 2023 10:40:59
%S A363860 0,0,1,0,0,0,1,1,0,0,1,0,1,0,1,0,0,1,2,0,0,0,2,0,0,0,1,1,0,1,2,0,1,0,
%T A363860 1,0,0,1,1,0,1,0,3,0,0,0,1,1,1,0,1,1,1,0,2,0,0,1,1,0,0,0,3,0,0,0,3,2,
%U A363860 0,0,1,0,1,1,1,0,0,1,2,0,0,0,2,0,2,0,2,1,0,0,2,0,2,0,1,1,0,1,1,0
%N A363860 Number of divisors of 7*n-1 of form 7*k+4.
%C A363860 Also number of divisors of 7*n-1 of form 7*k+5.
%F A363860 a(n) = A363806(7*n-1) = A363807(7*n-1).
%F A363860 G.f.: Sum_{k>0} x^(5*k-2)/(1 - x^(7*k-3)).
%F A363860 G.f.: Sum_{k>0} x^(4*k-1)/(1 - x^(7*k-2)).
%t A363860 a[n_] := DivisorSum[7*n - 1, 1 &, Mod[#, 7] == 4 &]; Array[a, 100] (* _Amiram Eldar_, Jun 25 2023 *)
%o A363860 (PARI) a(n) = sumdiv(7*n-1, d, d%7==4);
%Y A363860 Cf. A363806, A363807.
%K A363860 nonn
%O A363860 1,19
%A A363860 _Seiichi Manyama_, Jun 24 2023