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A164570 Primes p such that 8*p-3 and 8*p+3 are also prime numbers. 1
2, 5, 7, 13, 47, 103, 107, 127, 163, 233, 293, 337, 383, 433, 443, 467, 503, 673, 677, 733, 797, 877, 1087, 1093, 1153, 1217, 1223, 1307, 1637, 1933, 2053, 2087, 2137, 2423, 2477, 2543, 2633, 2687, 2857, 2917, 3163, 3373, 3407, 3467, 3767, 3793, 3877 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of A023229. [R. J. Mathar, Aug 26 2009]

Primes of the form A087695(k)/8. [R. J. Mathar, Aug 26 2009]

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

EXAMPLE

For p=2, 8*2-3=13 and 8*2+3=19 are prime numbers, which adds p=2 to the sequence

For p=5, 8*5-3=37 and 8*5+3=43 are prime numbers, which adds p=5 to the sequence.

MATHEMATICA

lst={}; Do[p=Prime[n]; If[PrimeQ[8*p-3]&&PrimeQ[8*p+3], AppendTo[lst, p]], {n, 7!}]; lst

Select[Prime[Range[1000]], And@@PrimeQ/@{8 # + 3, 8 # - 3}&] (* Vincenzo Librandi, Apr 09 2013 *)

PROG

(MAGMA) [p: p in PrimesUpTo(3000) | IsPrime(8*p-3) and IsPrime(8*p+3)]; // Vincenzo Librandi, Apr 09 2013

CROSSREFS

Cf. A023212, A023217, A023224, A023230, A023239, A060212, A106015, A124098, A125272, A127430, A153768, A164566, A164567, A164568, A164569.

Sequence in context: A141112 A053647 A023242 * A265811 A265793 A126338

Adjacent sequences:  A164567 A164568 A164569 * A164571 A164572 A164573

KEYWORD

nonn,easy

AUTHOR

Vladimir Joseph Stephan Orlovsky, Aug 16 2009

EXTENSIONS

Comments turned into examples by R. J. Mathar, Aug 26 2009

STATUS

approved

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Last modified March 26 14:18 EDT 2019. Contains 321497 sequences. (Running on oeis4.)