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 A074258 Gaps between primes p such that 2p-1 is also prime. 0
 1, 4, 12, 12, 6, 42, 18, 42, 18, 42, 12, 18, 42, 36, 24, 6, 30, 12, 60, 60, 48, 30, 24, 6, 12, 42, 30, 36, 84, 18, 48, 60, 30, 30, 12, 60, 102, 66, 42, 18, 102, 30, 30, 72, 78, 18, 30, 102, 108, 144, 18, 60, 42, 6, 42, 42, 60, 30, 156, 72, 12, 6, 60, 90, 12, 72, 60 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..1000 PROG (PARI) my(lsgp=2); forprime (p=3, 3000, if (isprime(2*p-1), print1(p-lsgp, ", "); lsgp=p)) CROSSREFS First differences of A005382. Cf. A001223. Sequence in context: A247327 A238581 A063608 * A253137 A120213 A005886 Adjacent sequences:  A074255 A074256 A074257 * A074259 A074260 A074261 KEYWORD nonn,changed AUTHOR Jon Perry, Sep 20 2002 EXTENSIONS Offset corrected and terms a(34) and beyond from Andrew Howroyd, Jan 16 2020 STATUS approved

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Last modified January 18 01:05 EST 2020. Contains 330995 sequences. (Running on oeis4.)