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 A172071 Primes p such that either p - 5/2 -+ 7/2 is prime. 2

%I

%S 2,11,13,17,19,23,29,37,43,47,53,59,67,73,79,89,103,107,109,113,137,

%T 157,163,173,179,197,199,229,233,239,257,263,269,277,283,313,317,337,

%U 353,359,373,379,389,439,449,463,467,509,547,563,569,577,593,599,607,613

%N Primes p such that either p - 5/2 -+ 7/2 is prime.

%C Two together with values of p+6 where (p,p+6) are both prime.

%H Jinyuan Wang, <a href="/A172071/b172071.txt">Table of n, a(n) for n = 1..1000</a>

%e 2 is a term because 2 - 5/2 - 7/2 = -4 (nonprime) and 2 - 5/2 + 7/2 = 3 (prime).

%p for n from 1 to 200 do p := ithprime(n) ; if isprime(p+1) <> isprime(p-6) then printf("%d,",p) ; end if; end do: # _R. J. Mathar_, Apr 24 2010

%Y Cf. A000040, A046117.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Jan 25 2010

%E Entries checked by _R. J. Mathar_, Apr 24 2010

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Last modified April 25 18:12 EDT 2019. Contains 322461 sequences. (Running on oeis4.)