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 A172070 Primes p such that either p-1/2-+5/2, but not both, is prime. 0
 3, 11, 17, 29, 41, 59, 71, 101, 107, 137, 149, 179, 191, 197, 227, 239, 269, 281, 311, 347, 419, 431, 461, 521, 569, 599, 617, 641, 659, 809, 821, 827, 857, 881, 1019, 1031, 1049, 1061, 1091, 1151, 1229, 1277, 1289, 1301, 1319, 1427, 1451, 1481, 1487, 1607, 1619, 1667, 1697, 1721, 1787, 1871, 1877 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Lesser of twin primes without 5. LINKS EXAMPLE a(1)=3 because 3-1/2-5/2=0(nonprime) and 3-1/2+5/2=5(prime). CROSSREFS Cf. A001359. Sequence in context: A126691 A154613 A109654 * A038986 A276848 A194800 Adjacent sequences:  A172067 A172068 A172069 * A172071 A172072 A172073 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Jan 25 2010 EXTENSIONS Entries checked by R. J. Mathar, May 02 2010 More terms from and definition clarified by Harvey P. Dale, Jul 22 2014 STATUS approved

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Last modified March 22 04:32 EDT 2019. Contains 321406 sequences. (Running on oeis4.)