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A245640 Prime numbers P such that 24*P^3-1 is also prime. 4
2, 3, 5, 7, 13, 17, 43, 61, 67, 73, 97, 127, 131, 137, 167, 241, 281, 307, 353, 433, 463, 467, 541, 557, 631, 641, 647, 653, 661, 673, 683, 821, 853, 857, 907, 911, 991, 1033, 1063, 1103, 1117, 1123, 1291, 1307, 1433, 1453, 1511, 1523, 1553, 1567, 1571, 1597, 1601, 1607 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

24*2^3-1=191 prime so a(1)=2.

24*3^3-1=647 prime so a(2)=3.

MATHEMATICA

Select[Prime[Range[300]], PrimeQ[24 #^3 - 1] &] (* Vincenzo Librandi, Sep 07 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 24*p(n)^3-1, t

IF ISPRP THEN GOTO a

GOTO loop1

LABEL a

WRITE myf, t

GOTO loop1

(PARI) select(p->isprime(24*p^3-1), primes(300)) \\ Colin Barker, Jul 28 2014

(MAGMA) [p: p in PrimesUpTo(1700)| IsPrime(24*p^3-1)]; // Vincenzo Librandi, Sep 07 2014

CROSSREFS

Cf. A245639, A245641.

Sequence in context: A053435 A096478 A076047 * A178766 A077316 A082011

Adjacent sequences:  A245637 A245638 A245639 * A245641 A245642 A245643

KEYWORD

nonn,easy

AUTHOR

Pierre CAMI, Jul 28 2014

STATUS

approved

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Last modified October 23 23:51 EDT 2019. Contains 328379 sequences. (Running on oeis4.)