A263874 Integers for which the smallest k in A067760 such that n + 2^k is prime increases.

1, 7, 23, 31, 47, 61, 139, 271, 287, 773, 2131, 40291

Offset: 1

Author

Arkadiusz Wesolowski, Oct 28 2015

Keywords

• nonn
• hard
• more

Links

• mersenneforum.org, Five or Bust - The Dual Sierpinski Problem

Crossrefs

Cf. A067760, A123252.

A263875 gives the record values.

Programs

PARI

a=1; forstep(n=1, 773, 2, k=1; while(!ispseudoprime(n+2^k), k++); if(k+1>a, print1(n, ", "); a=k+1));