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 A342673 #8 Mar 23 2021 16:17:20
%S A342673 1,2,3,1,1,6,1,8,1,2,1,6,1,2,3,1,1,2,1,4,3,2,1,24,1,2,3,4,1,6,1,4,3,2,
%T A342673 1,1,1,2,3,40,1,6,1,2,1,2,1,6,7,2,3,26,1,6,1,8,3,2,1,12,1,2,3,1,1,6,1,
%U A342673 4,3,2,1,8,1,2,3,4,7,6,1,8,1,2,1,12,5,2,3,8,1,2,1,2,3,2,1,24,1,14,1,1,1,6,1,8,3
%N A342673 a(n) = gcd(n, sigma(A003961(n))), where A003961 is fully multiplicative with a(prime(k)) = prime(k+1), and sigma is the sum of divisors of n.
%H A342673 Antti Karttunen, <a href="/A342673/b342673.txt">Table of n, a(n) for n = 1..16384</a>
%H A342673 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%H A342673 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A342673 a(n) = gcd(n, A003973(n)) = gcd(n, A000203(A003961(n))).
%o A342673 (PARI)
%o A342673 A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
%o A342673 A342673(n) = gcd(n,sigma(A003961(n)));
%Y A342673 Cf. A000203, A003961, A003973, A342671.
%Y A342673 Cf. also A336850, A341528.
%K A342673 nonn
%O A342673 1,2
%A A342673 _Antti Karttunen_, Mar 20 2021