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A064936
Primes p such that gcd(p, prime(p)^2 - 1) does not equal 1.
0
2, 3, 5, 181, 40087, 251737, 335276334037181, 115423110870118057, 115423110870118561
OFFSET
1,1
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)
EXAMPLE
5 belongs in the sequence because gcd(5, P_5^2 -1) = gcd(5, 120) = 5.
MATHEMATICA
Do[ If[ GCD[ Prime[n], Prime[ Prime[n]]^2 - 1] != 1, Print[ Prime[n]] ], {n, 1, 10^6} ]
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert G. Wilson v, Oct 26 2001
STATUS
approved