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 A137150 #9 Jul 30 2022 09:47:23
%S A137150 1,3,60,1260,6720,90720,9979200,1037836800,10897286400,163459296000,
%T A137150 59281238016000,15205637551104000,202741834014720000,
%U A137150 5109094217170944000,3231502092360622080000,31022420086661971968000
%N A137150 Degree of Lagrange resolvent of polynomial of composite degree.
%C A137150 Ratio: degree of symmetric group of composite order n divided by order metacyclic group of composite order n.
%H A137150 Vincenzo Librandi, <a href="/A137150/b137150.txt">Table of n, a(n) for n = 1..300</a>
%F A137150 a(n) = n!/(n EulerPhi[n]) for composite n A058161 = A137149 + A137150.
%t A137150 a = {}; Do[If[PrimeQ[n],[null], AppendTo[a, n!/(n EulerPhi[n])]], {n, 1, 30}]; a
%t A137150 With[{nn=30},#!/(# EulerPhi[#])&/@Complement[Range[nn],Prime[Range[ PrimePi[ nn]]]]] (* _Harvey P. Dale_, Jul 05 2014 *)
%Y A137150 Cf. A058161, A137149.
%K A137150 nonn
%O A137150 1,2
%A A137150 _Artur Jasinski_, Jan 23 2008