A228452 Smallest prime k such that k*2^n-1 , k*2^n-1+2*j , k*2^n-1+4*j or k*2^n-1-2*j , k*2^n-1 , k*2^n-1+2*j are consecutive primes in arithmetic progression for some j.

3, 53, 19, 3, 19, 593, 313, 113, 1699, 1163, 31, 4217, 31, 47, 7993, 1013, 631, 347, 3793, 3923, 397, 353, 2551, 83, 2719, 971, 3709, 6827, 6361, 593, 2053, 16073, 2719, 2753, 4441, 8663, 31, 131, 61, 5867, 379, 587, 9631, 1907, 8581, 23, 15739, 4049, 2281

Offset: 1

Author

Pierre CAMI, Oct 27 2013

Keywords

• nonn

Examples

			53*2^2-1-12=199, 53*2^2-1=211 and 53*2^2-1+12=223, so a(2)=53.
19*2^3-1=151, 19*2^3-1+6=157 and 19*2^3-1+12=163, so a(3)=19.
		

Links

• Pierre CAMI, Table of n, a(n) for n = 1..350
• Pierre CAMI, PFGW Script

Crossrefs

Cf. A227888.