A078583 Numbers k such that 2^k - prime(k) is prime.

3, 11, 19, 24, 26, 61, 96, 175, 189, 312, 483, 741, 4741, 7082, 8421, 10695, 14802, 18824, 18892, 20655, 21653, 39937, 84160

Offset: 1

Author

Robert G. Wilson v, Nov 30 2002

Keywords

• nonn
• more

Comments

a(23) is greater than 50000 - Sam Handler (sam_5_5_5_0(AT)yahoo.com), Dec 05 2004

a(24) is greater than 200000. - Michael S. Branicky, Jan 03 2025

Crossrefs

Corresponding prime(k) are in A078686.

Cf. A077375.

Programs

Mathematica

Do[ If[ PrimeQ[2^n - Prime[n]], Print[n]], {n, 1, 10^5}]

Extensions

a(14)-a(22) from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Dec 05 2004

a(23) from Michael S. Branicky, Dec 31 2024