A245641 Prime numbers P such that 8*P^2-1 and 24*P^3-1 are also primes.

2, 3, 5, 17, 67, 137, 241, 353, 541, 641, 907, 1033, 1307, 1453, 1607, 1621, 1733, 1811, 2053, 2243, 2273, 2377, 2621, 2963, 3677, 3701, 3881, 3943, 4861, 5261, 5647, 6101, 6823, 7723, 7877, 8081, 8101, 8447, 8923, 9467, 10111, 10223, 11483, 11617, 12161, 12203, 12227, 12457

Offset

1,1

Comments

Intersection of A245639 and A245640.

Links

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

Mathematica

Select[Prime[Range[2000]], PrimeQ[8 #^2 - 1] && PrimeQ[24 #^3 - 1] &] (* Vincenzo Librandi, Sep 08 2014 *)

Prog

(PFGW & SCRIPT)
SCRIPT
DIM n, 0
DIMS t
OPENFILEOUT myf, a(n).txt
LABEL loop1
SET n, n+1
SETS t, %d, %d\,; n; p(n)
PRP 8*n^2-1, t
IF ISPRP THEN GOTO a
GOTO loop1
LABEL a
PRP 24*n^3-1, t
IF ISPRP THEN GOTO b
GOTO loop1
LABEL b
WRITE myf, t
GOTO loop1
(PARI) select(p->isprime(8*p^2-1)&&isprime(24*p^3-1), primes(3000)) \\ Colin Barker, Jul 28 2014
(Magma) [p: p in PrimesUpTo(15000)| IsPrime(8*p^2-1)and IsPrime(24*p^3-1)]; // Vincenzo Librandi, Sep 08 2014

Crossrefs

Cf. A245639, A245640.

Sequence in context: A103074 A173236 A268209 * A082979 A065952 A308316

Adjacent sequences: A245638 A245639 A245640 * A245642 A245643 A245644

Keyword

nonn

Author

Pierre CAMI, Jul 28 2014

Status

approved