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 A130640 Numbers n such that either 2^n+p(n) or 2^n-p(n) is prime, where p(n) denotes the n-th prime. 0
 2, 3, 4, 5, 11, 12, 13, 14, 19, 23, 24, 26, 57, 61, 96, 106, 175, 189, 226, 227, 311, 312, 373, 483, 741, 1046, 1298, 1787, 1952, 2130, 2285, 2670, 3254, 3642, 4369, 4741, 7082, 8421, 10695, 13559, 14802, 18824, 18892, 20655 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 2^5 + p(5) = 32 + 11 = 43; 43 is prime, hence 5 is in the sequence. 2^11 - p(11) = 2048 - 31 = 2017; 2017 is prime, therefore 11 is in the sequence. MATHEMATICA Select[Range[2000], PrimeQ[2^# - Prime[ # ]] || PrimeQ[2^# + Prime[ # ]] &] CROSSREFS Cf. A078583, A077375. Sequence in context: A171592 A084545 A069908 * A214653 A116068 A104420 Adjacent sequences:  A130637 A130638 A130639 * A130641 A130642 A130643 KEYWORD nonn AUTHOR J. M. Bergot, Jun 19 2007 EXTENSIONS Edited and extended by Stefan Steinerberger, Jun 24 2007 STATUS approved

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Last modified June 19 04:51 EDT 2013. Contains 226390 sequences.