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A253939 Primes p such that (p^2 + 5)/6, (p^4 + 5)/6 and (p^6 + 5)/6 are prime. 3
7309, 45361, 67103, 97777, 128521, 149381, 374669, 543313, 656459, 872747, 940913, 1110817, 1219877, 1288603, 1324567, 1599319, 1629809, 2006677, 2129527, 2495501, 2544121, 2735839, 2763053, 2786363, 2856167, 3145661, 3428839, 3585149, 4063877, 4115971 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..125

MATHEMATICA

Select[Prime[Range[10^7]], PrimeQ[(#^2 + 5) / 6] &&PrimeQ[(#^4 + 5) / 6] &&PrimeQ[(#^6 + 5) / 6] &] (* Vincenzo Librandi, Jan 21 2015 *)

Select[Prime[Range[3*10^5]], AllTrue[(#^{2, 4, 6}+5)/6, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Mar 10 2016 *)

PROG

(MAGMA) [p: p in PrimesUpTo(10^7) | IsPrime((p^2+5) div 6) and IsPrime((p^4+5) div 6) and IsPrime((p^6+5) div 6)]; // Vincenzo Librandi, Jan 21 2015

CROSSREFS

Subsequence of A253925. Cf. A118915, A247478.

Sequence in context: A031799 A250638 A206080 * A116248 A140078 A321504

Adjacent sequences:  A253936 A253937 A253938 * A253940 A253941 A253942

KEYWORD

nonn

AUTHOR

Zak Seidov, Jan 20 2015

STATUS

approved

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Last modified February 20 21:29 EST 2019. Contains 320350 sequences. (Running on oeis4.)