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 A023225 Numbers n such that n and 7n + 6 are both prime. 16
 5, 11, 13, 19, 23, 31, 41, 43, 59, 61, 71, 83, 103, 109, 113, 149, 151, 173, 179, 199, 211, 223, 229, 233, 241, 263, 269, 281, 283, 353, 373, 379, 383, 389, 419, 421, 431, 433, 439, 479, 499, 503, 541, 563, 569, 571, 593, 613, 619, 631, 641, 643, 683, 709, 719, 739, 761 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS John Cerkan, Table of n, a(n) for n = 1..10000 MATHEMATICA Select[Prime[Range[2000]], PrimeQ[7 # + 6]&] (* Vincenzo Librandi, Feb 02 2014 *) PROG (MAGMA) [n: n in [0..1000] | IsPrime(n) and IsPrime(7*n+6)]; // Vincenzo Librandi, Nov 20 2010 (PARI) is(n)=isprime(7*n+6)&&isprime(n) \\ Charles R Greathouse IV, Jul 02 2013 CROSSREFS Sequence in context: A079019 A191034 A222219 * A206581 A292940 A098085 Adjacent sequences:  A023222 A023223 A023224 * A023226 A023227 A023228 KEYWORD nonn,easy AUTHOR STATUS approved

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Last modified January 23 22:36 EST 2020. Contains 331177 sequences. (Running on oeis4.)