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A190423
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Primes p such that the least k with p+k and p+2k both prime sets a new record.
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2
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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
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OFFSET
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1,1
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COMMENTS
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This sequence is conjectured to be infinite, but this is expected to be roughly as hard as the twin prime conjecture.
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LINKS
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Donovan Johnson, Table of n, a(n) for n = 1..60
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PROG
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(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)))
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CROSSREFS
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Cf. A120627, A190424.
Sequence in context: A032027 A005383 A175257 * A198636 A172023 A188583
Adjacent sequences: A190420 A190421 A190422 * A190424 A190425 A190426
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KEYWORD
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nonn
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AUTHOR
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Charles R Greathouse IV, May 10 2011
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STATUS
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approved
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