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 A359943 #11 Aug 09 2023 00:52:52 %S A359943 1,3,1,3,1,3,1,3,10,3,1,3,1,3,1,3,1,12,1,3,1,3,1,3,1,3,10,31,1,3,1,3, %T A359943 1,3,1,12,1,3,1,3,1,3,1,3,10,3,1,3,1,3,1,3,1,12,1,31,1,3,1,3,1,3,10,3, %U A359943 66,3,1,3,1,3,1,12,1,3,1,3,1,3,1,3,10,3,1,31,1,3 %N A359943 a(n) = Sum_{d|n, d-1 is cube} d. %F A359943 G.f.: Sum_{k>=0} (k^3+1) * x^(k^3+1)/(1 - x^(k^3+1)). %t A359943 a[n_] := DivisorSum[n, # &, IntegerQ[Surd[#-1, 3]] &]; Array[a, 100] (* _Amiram Eldar_, Aug 09 2023 *) %o A359943 (PARI) a(n) = sumdiv(n, d, ispower(d-1, 3)*d); %Y A359943 Cf. A001093, A113061, A359937, A359942, A359944. %K A359943 nonn %O A359943 1,2 %A A359943 _Seiichi Manyama_, Jan 19 2023