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A049002 Primes of form p^2 - 2, where p is prime. 22
2, 7, 23, 47, 167, 359, 839, 1367, 1847, 2207, 3719, 5039, 7919, 10607, 11447, 16127, 17159, 19319, 29927, 36479, 44519, 49727, 54287, 57119, 66047, 85847, 97967, 113567, 128879, 177239, 196247, 201599, 218087, 241079, 273527, 292679, 323759 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A062326(n)^2-2. - Zak Seidov, Apr 29 2015

EXAMPLE

127^2 - 2 = 16127.

MATHEMATICA

f[n_]:=n^2-2; lst={}; Do[p=Prime[n]; If[PrimeQ[f[p]], AppendTo[lst, f[p]]], {n, 7!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jul 16 2009 *)

Select[Prime[Range[150]]^2 - 2, PrimeQ] (* Vincenzo Librandi, Apr 29 2015 *)

PROG

(PARI) lista(nn) = forprime(p=1, nn, if (isprime(q=p^2-2), print1(q, ", "))); \\ Michel Marcus, Jan 08 2015

(Sage)

a = lambda p: p^2-2

[a(p) for p in primes(600) if is_prime(a(p))] # Bruno Berselli, Apr 29 2015

(MAGMA) [a: p in PrimesUpTo(1000) | IsPrime(a) where a is p^2-2 ]; // Vincenzo Librandi, Apr 29 2015

(Haskell)

a049002 n = a049002_list !! (n-1)

a049002_list = filter ((== 1) . a010051') a049001_list

-- Reinhard Zumkeller, Jul 30 2015

CROSSREFS

Primes in A049001.

Cf. A062326 (values of p).

Cf. A010051.

Sequence in context: A053705 A247175 A049001 * A247197 A195629 A011757

Adjacent sequences:  A048999 A049000 A049001 * A049003 A049004 A049005

KEYWORD

nonn,easy

AUTHOR

Herman H. Rosenfeld (herm3(AT)pacbell.net)

EXTENSIONS

More terms from James A. Sellers

STATUS

approved

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Last modified September 16 10:58 EDT 2019. Contains 327095 sequences. (Running on oeis4.)