A282565 a(n) is the largest prime p < 2^n such that p + 2^n is also prime.

3, 5, 13, 29, 43, 113, 223, 509, 907, 2003, 4051, 8171, 16333, 32603, 65437, 130649, 262027, 524261, 1048507, 2097047, 4194277, 8388209, 16776481, 33554201, 67108753, 134217401, 268435273, 536869631, 1073741719, 2147483549, 4294966477, 8589934307, 17179868383

Offset

2,1

Links

Table of n, a(n) for n=2..34.

Example

13 + 16 (2^4) = 29  (prime).
29 + 32 (2^5) = 61  (prime).
43 + 64 (2^6) = 107 (prime).

Crossrefs

Cf. A000040, A000079.

Sequence in context: A147196 A110225 A065047 * A295617 A290113 A238216

Adjacent sequences: A282562 A282563 A282564 * A282566 A282567 A282568

Keyword

nonn

Author

Emre APARI, Feb 18 2017

Status

approved