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 A020476 #29 Mar 25 2023 17:04:35 %S A020476 1,30154214043975990969,76630991932799573643, %T A020476 3590918978816938469301573291605,68804810614900760202830061602802, %U A020476 527113576787083306927808065765554478755087 %N A020476 Numbers k such that the sum of divisors of k^3 is a cube. %C A020476 WARNING: the listed terms are not proved to be in order. According to Basso (2017), it is not even proved that a(2) = 30154214043975990969. - _Max Alekseyev_, Mar 25 2023 %H A020476 Andrea Basso, <a href="https://fse.studenttheses.ub.rug.nl/15363/1/BSc_Math_2017_Basso_A.pdf">Power values of the sigma function</a>, Bachelor’s Project Mathematics, University of Gronigen, July 2017. See Appendix D p. 36. %o A020476 (PARI) isok(n) = ispower(sigma(n^3), 3); \\ _Michel Marcus_, Jul 19 2017 %Y A020476 Cf. A000578, A175926. %K A020476 nonn,more %O A020476 1,2 %A A020476 _David W. Wilson_