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 A306682 #12 Sep 08 2022 08:46:21 %S A306682 1,1,1,1,1,12,1,1,1,2,1,4,1,4,3,1,1,3,1,2,1,4,1,12,1,2,1,56,1,72,1,1, %T A306682 3,2,1,1,1,4,1,10,1,48,1,4,3,4,1,4,1,1,9,2,1,24,1,8,1,2,1,24,1,4,1,1, %U A306682 1,144,1,2,3,16,1,3,1,2,1,4,1,24,1,2,1,2,1 %N A306682 a(n) = gcd(sigma(n), pod(n)) where sigma(k) = the sum of the divisors of k (A000203) and pod(k) = the product of the divisors of k (A007955). %C A306682 See A324527(n) = the smallest numbers k such that a(k) = n. %H A306682 Antti Karttunen, <a href="/A306682/b306682.txt">Table of n, a(n) for n = 1..16384</a> %H A306682 Antti Karttunen, <a href="/A306682/a306682.txt">Data supplement: n, a(n) computed for n = 1..65537</a> %F A306682 a(n) = 1 for numbers in A014567. %F A306682 a(n) = tau(n) for numbers in A324526. %e A306682 For n=6: a(6) = gcd(tau(6), pod(6)) = gcd(4, 36) = 4. %o A306682 (Magma) [GCD(SumOfDivisors(n), &*[d: d in Divisors(n)]): n in [1.. 100]] %o A306682 (PARI) a(n) = my(d=divisors(n)); gcd(vecsum(d), vecprod(d)); \\ _Michel Marcus_, Mar 05 2019 %Y A306682 Cf. A000005, A000203, A007955, A009205, A046642, A120736, A324526, A324527. %K A306682 nonn %O A306682 1,6 %A A306682 _Jaroslav Krizek_, Mar 05 2019