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A126148 Primes p such that pq+p+q is prime, where q is the next prime after p. 12
2, 3, 5, 11, 13, 17, 19, 23, 41, 43, 47, 59, 79, 83, 89, 101, 109, 113, 137, 163, 167, 173, 223, 229, 257, 311, 383, 389, 409, 419, 439, 443, 479, 521, 547, 557, 577, 593, 613, 643, 647, 683, 773, 797, 809, 811, 853, 953, 983, 1019, 1049, 1097, 1109, 1151, 1171 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

EXAMPLE

Take p = 13 and q = 17: product is 221 and sum is 30; add them to get 251, a prime. So 13 is a member.

MAPLE

a:=proc(n) if isprime(ithprime(n)*ithprime(n+1) +ithprime(n) +ithprime(n+1)) then ithprime(n) fi end: seq(a(n), n=1..250); # Emeric Deutsch, Mar 08 2007

MATHEMATICA

Prime@Select[Range[200], PrimeQ[Prime[ # ]Prime[ # + 1] + Prime[ # ] + Prime[ # + 1]] &] (* Ray Chandler, Mar 07 2007 *)

PROG

(PARI) v=List(); p=2; forprime(q=3, 1e4, if(isprime(p*q+p+q), listput(v, p)); p=q); Vec(v) \\ Charles R Greathouse IV, Jul 26 2012

CROSSREFS

Cf. A096342, A000040, A001043, A006094, A126199, A096342.

Sequence in context: A042997 A220815 A171600 * A264866 A038933 A042998

Adjacent sequences:  A126145 A126146 A126147 * A126149 A126150 A126151

KEYWORD

nonn,easy

AUTHOR

J. M. Bergot, Mar 07 2007

EXTENSIONS

Extended by Ray Chandler, Emeric Deutsch and Robert G. Wilson v, Mar 07 2007

STATUS

approved

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Last modified May 25 11:27 EDT 2020. Contains 334592 sequences. (Running on oeis4.)