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 A190423 Primes p such that the least k with p+k and p+2k both prime sets a new record. 2
 3, 5, 13, 37, 73, 179, 503, 757, 1223, 1249, 1831, 2003, 4051, 6991, 17483, 18353, 18457, 22567, 26993, 47129, 88327, 131357, 136753, 215753, 344293, 499673, 2499143, 3345877, 3984391, 4065461, 5062649, 5418421, 7933109, 8865331, 11339287, 12464401, 18606089 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This sequence is conjectured to be infinite, but this is expected to be roughly as hard as the twin prime conjecture. LINKS Donovan Johnson, Table of n, a(n) for n = 1..60 PROG (PARI) print1(r=3); forprime(p=5, 4e9, forstep(k=6, 9e9, 6, if(isprime(p+k)&isprime(p+2*k), if(k>r, r=k; print1(", "p)); break))) CROSSREFS Cf. A120627, A190424. Sequence in context: A032027 A005383 A175257 * A198636 A172023 A188583 Adjacent sequences:  A190420 A190421 A190422 * A190424 A190425 A190426 KEYWORD nonn AUTHOR Charles R Greathouse IV, May 10 2011 STATUS approved

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Last modified May 19 17:43 EDT 2013. Contains 225436 sequences.