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%I #7 Oct 20 2013 10:22:42
%S 43,73,103,109,139,151,181,193,199,229,241,271,283,313,349,421,433,
%T 463,523,571,601,619,643,661,811,823,829,859,883,1021,1033,1051,1063,
%U 1093,1153,1231,1291,1303,1321,1429,1453,1483,1489,1609,1621,1669,1699,1723
%N Greater twin prime p such that 2^p-1 is composite.
%C Look at all twin primes (p1, p2); if 2^p2 - 1 is composite print p2.
%H Harvey P. Dale, <a href="/A087699/b087699.txt">Table of n, a(n) for n = 0..420</a>
%t Transpose[Select[Partition[Prime[Range[300]],2,1],Last[#]-First[#] == 2&&!PrimeQ[2^Last[#]-1]&]][[2]] (* _Harvey P. Dale_, Oct 20 2013 *)
%o (PARI) twopm1(n) = { forprime(x=2,n, y=2^x-1; if(!isprime(y) && isprime(x-2), print1(x",") ) ) }
%K easy,nonn
%O 0,1
%A _Cino Hilliard_, Oct 25 2003
%E Corrected and extended by _Ray Chandler_, Nov 07 2003