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A120364 Primes p such that p^2-p-1 and p^2-p+1 are twin primes. 5
3, 7, 67, 139, 379, 457, 1201, 1381, 1549, 1567, 1747, 1789, 2137, 2557, 2647, 2731, 4057, 4159, 4447, 4561, 5179, 5641, 6397, 9157, 9661, 9829, 9967, 10369, 11467, 11677, 12487, 12781, 13339, 13399, 15241, 17299, 17977, 19207, 19417, 19429 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

One more than the entries of (A006093 intersect A088485). - Danny Rorabaugh, May 15 2017

LINKS

Pierre CAMI, Table of n, a(n) for n = 1..10000

EXAMPLE

3*3-3-1=5 3*3-3+1=7, 5 and 7 twin primes so a(1)=3;

5*5-5-1=19 5*5-5+1=21 composite;

7*7-7-1=41 7*7-7+1=43, 41 and 43 twin primes so a(2)=7.

MATHEMATICA

Select[Prime[Range[2500]], PrimeQ[ #^2 - # - 1] && PrimeQ[ #^2 - # + 1] &] (* Stefan Steinerberger, Jul 22 2006 *)

CROSSREFS

Cf. A088483, A088485.

Sequence in context: A110433 A219845 A041817 * A088797 A165589 A184316

Adjacent sequences:  A120361 A120362 A120363 * A120365 A120366 A120367

KEYWORD

nonn

AUTHOR

Pierre CAMI, Jun 26 2006

EXTENSIONS

More terms from Stefan Steinerberger and Rick L. Shepherd, Jul 22 2006

STATUS

approved

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Last modified October 16 13:51 EDT 2019. Contains 328093 sequences. (Running on oeis4.)