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 A349741 #9 Nov 29 2021 01:39:48 %S A349741 1,1,1,1,1,2,1,2,4,4,1,32,1,6,256,16,1,96,1,1024,2304,10,1,16384,256, %T A349741 12,2304,13824,1,524288,1,2048,102400,16,5308416,14155776,1,18,589824, %U A349741 134217728,1,63700992,1,1024000,86973087744,22,1,8589934592,46656,1310720 %N A349741 a(n) = Product_{k=1..n-1} phi(gcd(n,k)). %F A349741 a(n) = Product_{d|n, d < n} phi(d)^phi(n/d). %t A349741 Table[Product[EulerPhi[GCD[n, k]], {k, 1, n - 1}], {n, 1, 50}] %o A349741 (PARI) a(n) = prod(k=1, n-1, eulerphi(gcd(n, k))); \\ _Michel Marcus_, Nov 28 2021 %Y A349741 Cf. A000010, A001088, A029935, A029940, A046022 (positions of 1's), A051190. %K A349741 nonn %O A349741 1,6 %A A349741 _Ilya Gutkovskiy_, Nov 28 2021