A335266 Numbers k such that b(n) = 2*b(n - 1) + k is prime, where b(0) = 1 and k is the smallest positive number.

1, 1, 3, 3, 5, 5, 5, 11, 15, 7, 13, 7, 13, 31, 13, 9, 5, 21, 3, 21, 51, 17, 9, 39, 15, 3, 57, 27, 3, 15, 35, 11, 39, 55, 13, 27, 11, 35, 17, 11, 15, 13, 1, 13, 19, 75, 5, 23, 41, 9, 63, 63, 13, 25, 31, 21, 11, 9, 27, 11, 3, 31, 21, 35, 47, 33

Offset

0,3

Comments

Sequence b, with an offset change, corresponds to A110930. - Rémy Sigrist, Jul 18 2020

Links

Table of n, a(n) for n=0..65.

Mathematica

b[0] = 1; b[n_] := b[n] = NextPrime[2*b[n - 1]]; Table[b[n] - 2*b[n - 1], {n, 1, 66}] (* Amiram Eldar, Aug 18 2020 *)

Prog

(PARI) b=1; for(n = 1, 66, b = 2 * b; p = nextprime(b + 1); k = p - b; b = p; print1(k", "))

Crossrefs

Cf. A000040, A110930.

Sequence in context: A257371 A075260 A054847 * A067782 A318916 A035299

Adjacent sequences: A335263 A335264 A335265 * A335267 A335268 A335269

Keyword

nonn

Author

Dimitris Valianatos, May 29 2020

Status

approved