A130640 Numbers k such that either 2^k + prime(k) or 2^k - prime(k) is prime.

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, 21653, 33418, 39937, 66830, 84160

Offset: 1

Author

J. M. Bergot, Jun 19 2007

Keywords

• nonn

Examples

			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.
		

Crossrefs

Union of A077375 and A078583.

Programs

Mathematica

Select[Range[2000], PrimeQ[2^# - Prime[ # ]] || PrimeQ[2^# + Prime[ # ]] &]

Extensions

Edited and extended by Stefan Steinerberger, Jun 24 2007

a(45)-a(49) from Michael S. Branicky, May 30 2025