A331205 a(n) = least prime of the form 2^m - 2^n + 1.

2, 3, 5, 549755813881, 17, 97, 193, 140737488355201, 257, 7681, 15361, 134215681, 12289, 8380417, 114689

Offset: 0

Author

Hugo Pfoertner, Jan 12 2020

Keywords

• nonn

Comments

a(15) = 2^447 - 2^15 + 1 is too large to be represented in the data.

Examples

			See A331204.
		

Links

• Hugo Pfoertner, Table of n, a(n) for n = 0..62

Crossrefs

Cf. A181692, A331204 (corresponding values of m).

Programs

PARI

for(n=0,14, for(m=n+1,oo, k=2^m-2^n+1; if(isprime(k), print1(k,", "); break)))