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%I #15 Mar 17 2018 23:10:29
%S 1,1,1,1,2,1,12,1,8,3,1440,1,17280,3,112,45,29030400,1,522547200,3,
%T 12800,945,4828336128000,1,38626689024,4725,512512000,2025,
%U 3796230997278720000,1,113886929918361600000,42525,10436608000,1403325,551910745571328,175
%N a(n) = A001783(n)/A038610(n).
%H T. D. Noe, <a href="/A128247/b128247.txt">Table of n, a(n) for n = 1..200</a>
%e The positive integers which are <= 10 and are coprime to 10 are 1,3,7,9. So a(10) = 1*3*7*9/lcm(1,3,7,9) = 189/63 = 3.
%t Table[s = Select[Range[1, n], GCD[#, n] == 1 &]; (Times @@ s)/(LCM @@ s), {n, 30}] (* _T. D. Noe_, Oct 04 2012 *)
%o (Sage)
%o def Gauss_factorial(N, n): return mul(j for j in (1..N) if gcd(j, n) == 1)
%o def L(N, n): return lcm([j for j in (1..N) if gcd(j, n) == 1])
%o def A128247(n): return Gauss_factorial(n, n)/L(n, n)
%o [A128247(n) for n in (1..34)] # _Peter Luschny_, Oct 02 2012
%Y Cf. A038610, A001783.
%K nonn
%O 1,5
%A _Leroy Quet_, May 03 2007
%E More terms from _Sean A. Irvine_, Jun 21 2011
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