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%I #8 Feb 11 2014 19:05:42
%S 3,3,3,3,3,3,3,23,3,131,3,67,7,3,43,461,523,3,1021,113,3877,5,19,1493,
%T 3,5,7,3187,5,593,2633,5,661,3371,179,3889,3,839,443,3023,1579,1613,
%U 251,139,751,3343,229,5233,4153
%N Begins the first chain of n consecutive primes whose product - 2 is prime.
%e 3 is the smallest prime in 3, 5, 7, 11 which is the first chain of four consecutive primes whose product - 2 is prime: 3 * 5 * 7 * 11 - 2 = 1153 (prime). Hence a(4) = 3.
%o (PARI) pchain(p, n) = {my(pp = p, i, q); for (i=1, n-1, q = nextprime(p+1); pp *= q; p = q;); return (pp-2);}
%o lista(nn) = {for (n = 2, nn, p = 3; while (! isprime(pchain(p, n)), p = nextprime(p+1);); print1(p, ", "););} \\ _Michel Marcus_, May 18 2013
%K nonn
%O 2,1
%A _Joseph L. Pe_, Jun 12 2003
%E More terms from _Michel Marcus_, May 18 2013
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