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 A091567 Primes p such that p^2-p-1 is prime. 21
 3, 5, 7, 11, 17, 29, 31, 47, 61, 67, 71, 97, 101, 127, 131, 139, 149, 181, 197, 241, 269, 307, 331, 359, 379, 397, 409, 419, 421, 449, 457, 479, 487, 491, 599, 607, 617, 619, 641, 647, 677, 709, 751, 787, 839, 857, 907, 947, 967, 977, 997, 1051, 1061, 1091 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988 Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta,UTET, CittaStudiEdizioni, Milano 1997 LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 MATHEMATICA Select[Prime[Range[250]], PrimeQ[ #^2-#-1]&] - Alexander Adamchuk, Jul 27 2006 PROG (PARI) isA091567(n)=isprime(n) && isprime(n^2-n-1) - Michael B. Porter, May 12 2010 CROSSREFS Cf. A053182 (p^2+p+1 prime), A053184 (p^2+p-1 prime), A065508 (p^2-p+1 prime). Cf. A091568 Primes of the form p^2-p-1, where p is prime from a(n). Sequence in context: A109543 A229168 A248714 * A241896 A076186 A092564 Adjacent sequences:  A091564 A091565 A091566 * A091568 A091569 A091570 KEYWORD nonn AUTHOR T. D. Noe, Jan 21 2004 STATUS approved

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Last modified October 15 20:04 EDT 2019. Contains 328037 sequences. (Running on oeis4.)