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%I #11 Oct 16 2018 20:09:29
%S 11,15,35,75,83,111,119,135,155,179,219,231,243,323,359,375,455,459,
%T 483,491,515,519,525,531,551,611,615,639,651,663,699,719,723,735,771,
%U 779,783,803,879,915,923,939,999,1043,1103,1119,1175,1199,1271,1323
%N Numbers n such that gcd(n!-1,2^n-1)>1.
%H G. C. Greubel, <a href="/A068483/b068483.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[2500], GCD[#! - 1, 2^# - 1] > 1 &] (* _G. C. Greubel_, Oct 15 2018 *)
%o (PARI) isok(n) = gcd(n!-1,2^n-1) > 1; \\ _Michel Marcus_, Oct 16 2018
%Y Cf. A000225 (2^n-1), A033312 (n!-1).
%Y Cf. A068480, A068481, A068482.
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, Mar 10 2002