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A126148 Primes p such that pq+p+q is prime, where q is the next prime after p. 9
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 *)

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 * A038933 A042998 A091317

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 December 18 08:30 EST 2014. Contains 252114 sequences.