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%I #12 Nov 06 2019 01:11:20
%S 1,1,2,2,8,2,30,12,32,10,270,12,792,72,144,336,5376,96,14688,432,1520,
%T 1600,96000,960,48576,7392,48384,7056,917280,720,2332800,172800,
%U 122880,122880,304128,31104,19595520,559872,1119744,262656,102435840,46080,258048000,3225600,3386880
%N Number of divisors of n! that are coprime to n.
%C a(p_i) < a(p_j) for i<j.
%H Andrew Howroyd, <a href="/A095997/b095997.txt">Table of n, a(n) for n = 1..1000</a>
%t f[n_] := Length[ Select[ Divisors[n! ], GCD[ #, n] == 1 &]]; Table[ f[n], {n, 33}]
%o (PARI) a(n)={if(n<=2, 1, numdiv(Mat(select(f->n%f[1], Col(factor(n!))))))} \\ _Andrew Howroyd_, Nov 05 2019
%Y Cf. A000142, A027423.
%K nonn
%O 1,3
%A _Robert G. Wilson v_, Jul 19 2004, based on a suggestion from _Leroy Quet_, Jun 18 2004
%E Terms a(34) and beyond from _Andrew Howroyd_, Nov 05 2019
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