A230487 Strong pseudoprimes k to base 2 such that either k-2 or k+2 is prime.

4681, 29341, 42799, 49141, 52633, 85489, 90751, 104653, 253241, 280601, 458989, 580337, 1004653, 1082401, 1207361, 1251949, 1302451, 1678541, 1907851, 1909001, 2419385, 2510569, 2811271, 3090091, 3539101, 5044033, 5049001, 5173601, 5489641, 5590621, 7177105

Offset: 1

Author

Shyam Sunder Gupta, Oct 20 2013

Keywords

• nonn

Examples

			4681 is a strong pseudoprime (base 2) and 4679 is prime. 253241 is a strong pseudoprime (base 2) and 253243 is prime.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..5001 from Shyam Sunder Gupta)

Crossrefs

Union of A230483 and A230484.

Cf. A001567, A001262, A230485.