A230485 Strong pseudoprimes n to base 2 such that n-2 and n+2 are primes.

3465253618401, 44202753561285411, 1640293473202755801, 10623546148468360251

Offset: 1

Author

Shyam Sunder Gupta, Oct 20 2013

Keywords

• nonn
• more
• hard

Comments

For all n, a(n)-2 is in A230810. - M. F. Hasler, Dec 08 2016

Examples

			3465253618401 is a strong pseudoprime (base 2) and 3465253618399 and 3465253618403 are primes.
		

Crossrefs

Cf. A001567, A057942, A001262, A230483, A230484.