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 A326073 #7 Jun 12 2019 19:14:00 %S A326073 1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,27,1,1,1,1,1,1, %T A326073 1,1,1,1,1,1,1,1,1,1,1,5,1,1,1,7,1,3,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, %U A326073 1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,5,1,1,1,1,5,1,1,1,7,5,1,1,1,1,1,1,1,1,1 %N A326073 a(n) = gcd(1+n-A020639(n), 1+sigma(n)-A020639(n)-n), where A020639 gives the smallest prime factor of n (and 1 for 1), and sigma is the sum of divisors of n. %H A326073 Antti Karttunen, <a href="/A326073/b326073.txt">Table of n, a(n) for n = 1..65537</a> %F A326073 a(n) = gcd(1+n-A020639(n), 1+A000203(n)-A020639(n)-n). %o A326073 (PARI) %o A326073 A020639(n) = if(1==n, n, factor(n)[1, 1]); %o A326073 A326073(n) = gcd(1+n-A020639(n), 1+sigma(n)-A020639(n)-n); %Y A326073 Cf. A000203, A020639, A326074. %Y A326073 Cf. also A009194, A325385, A325813, A325975, A326046, A326047, A326048, A326056, A326057, A326060, A326062, A326129, A326130, A326140, A326144, A326147. %K A326073 nonn %O A326073 1,6 %A A326073 _Antti Karttunen_, Jun 10 2019