cp's OEIS Frontend

A234695 Primes p with prime(p) - p + 1 also prime.

%I A234695 #12 Apr 06 2014 04:06:07
%S A234695 2,3,5,7,13,17,23,31,41,43,61,71,83,89,103,109,139,151,173,181,199,
%T A234695 211,223,241,271,277,281,293,307,311,317,337,349,353,367,463,499,541,
%U A234695 563,571,601,661,673,709,719,743,751,757,811,823,827,883,907,911,953
%N A234695 Primes p with prime(p) - p + 1 also prime.
%C A234695 By the conjecture in A234694, this sequence should have infinitely many terms.
%H A234695 Zhi-Wei Sun, <a href="/A234695/b234695.txt">Table of n, a(n) for n = 1..10000</a>
%H A234695 Z.-W. Sun, <a href="http://arxiv.org/abs/1402.6641">Problems on combinatorial properties of primes</a>, arXiv:1402.6641, 2014
%F A234695 a(n) = prime(A234852(n)). - _M. F. Hasler_, Dec 31 2013
%e A234695 a(1) = 2 since prime(2) - 1 = 2 is prime.
%e A234695 a(2) = 3 since prime(3) - 2 = 3 is prime.
%e A234695 a(3) = 5 since prime(5) - 4 = 7 is prime.
%e A234695 a(4) = 7 since prime(7) - 6 = 11 is prime.
%t A234695 n=0;Do[If[PrimeQ[Prime[Prime[k]]-Prime[k]+1],n=n+1;Print[n," ",Prime[k]]],{k,1,1000}]
%o A234695 (PARI) forprime(p=1,999,isprime(prime(p)-p+1)&&print1(p",")) \\ - _M. F. Hasler_, Dec 31 2013
%Y A234695 Cf. A000040, A014692, A234694.
%K A234695 nonn
%O A234695 1,1
%A A234695 _Zhi-Wei Sun_, Dec 29 2013