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 A363878 #11 Jun 25 2023 10:40:36
%S A363878 0,1,0,1,0,1,1,1,0,1,0,2,0,1,0,2,1,1,0,1,0,2,0,1,1,1,1,2,0,1,0,2,0,2,
%T A363878 0,1,1,1,0,2,0,2,1,2,0,1,1,1,0,1,0,4,0,1,0,1,1,1,0,2,1,2,1,2,0,1,1,1,
%U A363878 0,2,0,2,0,1,0,3,1,1,1,1,0,3,0,1,0,2,1,3,0,1,0,3,0,1,0,1,2,1,0,2
%N A363878 Number of divisors of 7*n-4 of form 7*k+2.
%C A363878 Also number of divisors of 7*n-4 of form 7*k+5.
%F A363878 a(n) = A363795(7*n-4) = A363807(7*n-4).
%F A363878 G.f.: Sum_{k>0} x^(5*k-3)/(1 - x^(7*k-5)).
%F A363878 G.f.: Sum_{k>0} x^(2*k)/(1 - x^(7*k-2)).
%t A363878 a[n_] := DivisorSum[7*n - 4, 1 &, Mod[#, 7] == 2 &]; Array[a, 100] (* _Amiram Eldar_, Jun 25 2023 *)
%o A363878 (PARI) a(n) = sumdiv(7*n-4, d, d%7==2);
%Y A363878 Cf. A363795, A363807.
%K A363878 nonn
%O A363878 1,12
%A A363878 _Seiichi Manyama_, Jun 25 2023