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%I #12 Mar 25 2022 14:36:19
%S 1,1,4,12,96,240,4320,20160,241920,1451520,36288000,159667200,
%T 5748019200,37362124800,697426329600,10461394944000,334764638208000,
%U 2134124568576000,115242726703104000,973160803270656000,29194824098119680000,510909421717094400000
%N Number of integers in {1, 2, ..., n!} that are coprime to n.
%F a(n) = (n-1)!*phi(n). - _Vladeta Jovovic_, Dec 28 2002
%e There are four integers in {1, 2, ..., 3! = 6} that are coprime to 3, i.e. 1, 2, 4, 5. Hence a(3) = 4.
%t h[n_] := Module[{l}, l = {}; For[i = 1, i <= n!, i++, If[GCD[i, n] == 1, l = Append[l, i]]]; l]; Table[Length[h[i]], {i, 1, 9}]
%Y Cf. A000010, A000142.
%K nonn,easy
%O 1,3
%A _Joseph L. Pe_, Oct 04 2002
%E More terms from _Michel ten Voorde_ Jun 20 2003