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%I #4 Mar 12 2015 19:15:48
%S 3,5,3,5,3,5,3,5,11,5,3,5,3,5,5,11,5,3,11,5,3,5,11,3,5,3,5,3,17,3,5,
%T 11,11,17,5,5,3,5,5,11,11,5,3,29,11,11,3,5,3,5,11,29,5,5,5,11,5,3,11,
%U 29,17,3,5,3,29,5,11,5,3,5,29,5,5,3,5,11,3,17,11,11,11,11,5,3,5,11,3,5,3,11
%N Smallest lower twin prime tp such that p + tp + 1 is prime. p ranges over the prime numbers.
%C Conjecture: For all primes p <= n there is always a lower twin prime L less than n such that p+L+1 is prime.
%e 29 is the 9th odd prime. 29+3+1, 29+5+1 are not prime. 29+11+1 is prime, so a(9) = 11 the smallest lower twin prime satisfying the definition for prime 29.
%o (PARI) g(n) = ct=0;for(x=2,n,p1=prime(x);for(y=1,n,p2=twinl(y);z=p1+p2+1;
%o if(isprime(z),ct++;print1(p2",");break)));ct
%K nonn
%O 1,1
%A _Cino Hilliard_, Nov 21 2008
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