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%I #18 Jun 06 2022 05:47:58
%S 2,11,19,43,67,131,163,179,227,347,419,443,491,523,563,571,619,683,
%T 691,739,787,947,1019,1051,1091,1123,1187,1291,1451,1499,1571,1579,
%U 1667,1723,1747,1867,1907,1931,2003,2131,2203,6043,2347,2371,2531,2579,2659
%N Values of gcd(k!+1,2^k+1) not equal to 1 taking k in increasing order.
%H Amiram Eldar, <a href="/A067660/b067660.txt">Table of n, a(n) for n = 1..10000</a>
%F If 2m+1 is prime and is in the sequence, 2m+1 = gcd(m!+1, 2^m+1).
%t Table[GCD[n!+1,2^n+1],{n,0,4000}]/.(1->Nothing) (* _Harvey P. Dale_, Aug 03 2018 *)
%o (PARI) for(k=0,3000,d=gcd(k!+1,2^k+1); if(d<>1,print1(d,",")))
%Y Cf. A068481.
%K nonn
%O 1,1
%A _Benoit Cloitre_, Feb 03 2002
%E Corrected and extended by _Rick L. Shepherd_, May 20 2002
%E Offset corrected by _Amiram Eldar_, Jun 06 2022
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