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A065017 p*q + p + q is prime, where (p, q=p+2) are twin primes. +0
1
23, 47, 167, 359, 1847, 3719, 10607, 19319, 97967, 177239, 273527, 657719, 1042439, 1104599, 1329407, 1515359, 1745039, 2042039, 4464767, 5013119, 5148359, 9740639, 11095559, 11377127, 12538679, 16024007, 16410599, 16752647 (list; graph; listen)
OFFSET

0,1

COMMENT

The resulting prime can never be a twin prime since the odd number preceding it is divisible by three and the following odd number is a perfect square.

FORMULA

p^2+4*p+2.

EXAMPLE

(3*5) + (3+5) = 23

MATHEMATICA

NextPrim[n_] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; k = 1; Do[k = NextPrim[k]; If[ PrimeQ[k + 2], p = k*(k + 2) + 2k + 2; If[ PrimeQ[p], Print[p]]], {n, 1, 700} ]

CROSSREFS

A049001, A049002

Sequence in context: A042050 A139857 A139900 this_sequence A140618 A042052 A136030

Adjacent sequences: A065014 A065015 A065016 this_sequence A065018 A065019 A065020

KEYWORD

nonn

AUTHOR

Stephan Wagler (stephanwagler(AT)aol.com), Nov 01 2001

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Last modified July 4 18:25 EDT 2008. Contains 140886 sequences.


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