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 A359239 #17 Aug 23 2023 08:41:48
%S A359239 0,1,0,2,0,2,0,2,1,2,0,2,0,4,0,2,0,2,2,2,0,3,0,4,0,2,0,2,2,4,0,2,0,4,
%T A359239 0,2,0,4,2,2,1,2,0,4,0,4,0,2,2,2,0,4,0,6,0,2,0,2,2,2,0,4,2,4,0,3,0,2,
%U A359239 2,4,0,2,0,6,0,2,0,4,2,4,0,2,0,4,2,4,0,2,2,2
%N A359239 Number of divisors of 3*n-2 of form 3*k+2.
%F A359239 a(n) = A001822(3*n-2).
%F A359239 G.f.: Sum_{k>0} x^(2*k)/(1 - x^(3*k-1)).
%t A359239 Table[Count[Divisors[3 n-2],_?(IntegerQ[(#-2)/3]&)],{n,100}] (* _Harvey P. Dale_, Apr 23 2023 *)
%t A359239 a[n_] := DivisorSum[3*n-2, 1 &, Mod[#, 3] == 2 &]; Array[a, 100] (* _Amiram Eldar_, Aug 23 2023 *)
%o A359239 (PARI) a(n) = sumdiv(3*n-2, d, d%3==2);
%o A359239 (PARI) my(N=100, x='x+O('x^N)); concat(0, Vec(sum(k=1, N, x^(2*k)/(1-x^(3*k-1)))))
%Y A359239 Cf. A001822, A359211, A359212.
%Y A359239 Cf. A359240, A359241.
%K A359239 nonn,easy
%O A359239 1,4
%A A359239 _Seiichi Manyama_, Dec 22 2022