A064936 Primes p such that gcd(p, prime(p)^2 - 1) does not equal 1.

2, 3, 5, 181, 40087, 251737, 335276334037181, 115423110870118057, 115423110870118561

Offset: 1

Author

Robert G. Wilson v, Oct 26 2001

Keywords

• nonn
• more

Comments

No further terms up to 41161739. - Harvey P. Dale, Dec 23 2011

No further terms up to 250000000. - Sean A. Irvine, Aug 01 2023

From Jason Yuen, Apr 21 2024: (Start)

Primes p such that prime(p)^2 == 1 (mod p).

Prime terms of A023143 or A045924.

No further terms up to 4*10^19. (End)

Examples

			5 belongs in the sequence because gcd(5, P_5^2 -1) = gcd(5, 120) = 5.
		

Crossrefs

Cf. A064830, A023143, A045924.

Programs

Mathematica

Do[ If[ GCD[ Prime[n], Prime[ Prime[n]]^2 - 1] != 1, Print[ Prime[n]] ], {n, 1, 10^6} ]