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A126148
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Primes p such that pq+p+q is prime, where q is the next prime after p.
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13
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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
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OFFSET
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1,1
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LINKS
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EXAMPLE
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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.
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MAPLE
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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
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MATHEMATICA
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Prime@Select[Range[200], PrimeQ[Prime[ # ]Prime[ # + 1] + Prime[ # ] + Prime[ # + 1]] &] (* Ray Chandler, Mar 07 2007 *)
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PROG
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(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
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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