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%I #8 Jan 19 2014 11:32:51
%S 7,11,31,67,179,193,197,281,347,349,563,599,757,1123,1453,1543,1933,
%T 1987,2083,2531,2971,3037,3259,3547,3583,3701,3919,4027,4483,5023,
%U 5581,5591,5647,5981,6449,7207,7297,7603,8291,9049
%N Odd primes p with prime(p-1) - (p-1) and prime(p-1) - 2*prime((p-1)/2) both prime.
%C By part (i) of the conjecture in A236138, this sequence should have infinitely many terms.
%H Zhi-Wei Sun, <a href="/A236143/b236143.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1) = 7 with prime(6) - 6 = 13 - 6 = 7 and prime(6) - 2*prime(3) = 13 - 2*5 = 3 both prime.
%t PQ[n_]:=n>0&&PrimeQ[n]
%t p[n_]:=PrimeQ[Prime[n-1]-(n-1)]&&PQ[Prime[n-1]-2*Prime[(n-1)/2]]
%t n=0;Do[If[p[Prime[k]],n=n+1;Print[n," ",Prime[k]]],{k,2,10^5}]
%o (PARI) s=[]; forprime(p=3, 10000, if(isprime(prime(p-1)-(p-1)) && isprime(prime(p-1)-2*prime((p-1)/2)), s=concat(s, p))); s \\ _Colin Barker_, Jan 19 2014
%Y Cf. A000040, A234695, A235925, A236075, A236119, A236138.
%K nonn
%O 1,1
%A _Zhi-Wei Sun_, Jan 19 2014
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