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A126148
Primes p such that pq+p+q is prime, where q is the next prime after p.
13
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
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
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