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 A046680 #16 May 08 2021 22:55:42 %S A046680 1,2,4,8,9,16,25,36,81,100,121,128,144,162,225,256,289,324,400,484, %T A046680 512,529,625,729,841,900,1024,1089,1156,1250,1296,1458,1681,1936,2025, %U A046680 2116,2209,2304,2401,2500,2601,2809,2916,3025,3364,3481,3600,4096,4356,4624 %N A046680 Numbers k such that the number of divisors of k and sum of cubes of divisors of k are relatively prime. %C A046680 It can be shown that this is a subsequence of A028982. %H A046680 Amiram Eldar, <a href="/A046680/b046680.txt">Table of n, a(n) for n = 1..10000</a> %t A046680 Select[Range[5000], CoprimeQ[DivisorSigma[0, #], DivisorSigma[3, #]] &] (* _Amiram Eldar_, Aug 08 2019 *) %o A046680 (PARI) isok(n) = gcd(numdiv(n), sigma(n, 3)) == 1; \\ _Michel Marcus_, Sep 24 2019 %Y A046680 Cf. A028982, A046678, A046679, A046681, A046683, A046685. %K A046680 nonn %O A046680 1,2 %A A046680 _Labos Elemer_