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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
Sequence in context: A283206 A084545 A069908 * A214653 A234142 A116068
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 March 19 06:25 EDT 2024. Contains 370953 sequences. (Running on oeis4.)