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 A367132 #14 Oct 29 2024 08:28:39
%S A367132 1,2,6,42,1656,3263442,10602458193600,113418211994216207709696000,
%T A367132 12864938683276241891688635987477942287491075520480800,
%U A367132 164509411410546646527417252552411687615280114012485682055193015232979290788896945885448940165659663840000
%N A367132 a(n) = phi(A000058(n)) where phi is the Euler totient function and A000058 is Sylvester's sequence.
%H A367132 Amiram Eldar, <a href="/A367132/b367132.txt">Table of n, a(n) for n = 0..10</a>
%H A367132 Wikipedia, <a href="https://en.wikipedia.org/wiki/Sylvester%27s_sequence#Divisibility_and_factorizations">Sylvester's sequence: Divisibility and factorizations</a>.
%F A367132 a(n) = A000010(A000058(n)).
%t A367132 EulerPhi[a[0] = 2; a[k_] := a[k - 1]^2 - a[k - 1] + 1; Table[a[k], {k, 0, 9}]] (* _Paul F. Marrero Romero_, Nov 19 2023 *)
%Y A367132 Cf. A000058, A000010, A091335.
%K A367132 nonn
%O A367132 0,2
%A A367132 _Sean A. Irvine_, Nov 05 2023