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

%I A245641 #14 Sep 08 2022 08:46:09
%S A245641 2,3,5,17,67,137,241,353,541,641,907,1033,1307,1453,1607,1621,1733,
%T A245641 1811,2053,2243,2273,2377,2621,2963,3677,3701,3881,3943,4861,5261,
%U A245641 5647,6101,6823,7723,7877,8081,8101,8447,8923,9467,10111,10223,11483,11617,12161,12203,12227,12457
%N A245641 Prime numbers P such that 8*P^2-1 and 24*P^3-1 are also primes.
%C A245641 Intersection of A245639 and A245640.
%H A245641 Pierre CAMI, <a href="/A245641/b245641.txt">Table of n, a(n) for n = 1..10000</a>
%t A245641 Select[Prime[Range[2000]], PrimeQ[8 #^2 - 1] && PrimeQ[24 #^3 - 1] &] (* _Vincenzo Librandi_, Sep 08 2014 *)
%o A245641 (PFGW & SCRIPT)
%o A245641 SCRIPT
%o A245641 DIM n,0
%o A245641 DIMS t
%o A245641 OPENFILEOUT myf,a(n).txt
%o A245641 LABEL loop1
%o A245641 SET n,n+1
%o A245641 SETS t,%d,%d\,;n;p(n)
%o A245641 PRP 8*n^2-1,t
%o A245641 IF ISPRP THEN GOTO a
%o A245641 GOTO loop1
%o A245641 LABEL a
%o A245641 PRP 24*n^3-1,t
%o A245641 IF ISPRP THEN GOTO b
%o A245641 GOTO loop1
%o A245641 LABEL b
%o A245641 WRITE myf,t
%o A245641 GOTO loop1
%o A245641 (PARI) select(p->isprime(8*p^2-1)&&isprime(24*p^3-1), primes(3000)) \\ _Colin Barker_, Jul 28 2014
%o A245641 (Magma) [p: p in PrimesUpTo(15000)| IsPrime(8*p^2-1)and IsPrime(24*p^3-1)]; // _Vincenzo Librandi_, Sep 08 2014
%Y A245641 Cf. A245639, A245640.
%K A245641 nonn
%O A245641 1,1
%A A245641 _Pierre CAMI_, Jul 28 2014