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A144620 Numbers n such that n and 19n+8 are both prime. 2
5, 17, 41, 59, 89, 167, 191, 239, 269, 281, 359, 449, 479, 491, 509, 521, 587, 617, 647, 701, 719, 821, 881, 911, 929, 971, 1031, 1181, 1217, 1259, 1289, 1307, 1361, 1367, 1559, 1601, 1697, 1709, 1721, 1787, 1877, 1889, 1907, 1931, 1949, 1997, 2039, 2129 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

For n=5, 19*5+8=103; n=269, 19*269+8=5119.

MAPLE

a := proc (n) if isprime(n) = true and isprime(19*n+8) = true then n else end if end proc: seq(a(n), n = 1 .. 2300); [From Emeric Deutsch, Jan 27 2009]

MATHEMATICA

Select[Prime[Range[400]], PrimeQ[#] &&PrimeQ[19#+8] &] (* Vincenzo Librandi, Aug 30 2012 *)

PROG

(MAGMA) [p: p in PrimesUpTo(2500)|IsPrime(19*p+8)] // Vincenzo Librandi, Aug 30 2012

CROSSREFS

Cf. A141873, A144619.

Sequence in context: A011931 A260981 A078866 * A217622 A269728 A091864

Adjacent sequences:  A144617 A144618 A144619 * A144621 A144622 A144623

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Jan 15 2009

EXTENSIONS

Extended by Emeric Deutsch, Jan 27 2009

STATUS

approved

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Last modified August 18 16:13 EDT 2018. Contains 313833 sequences. (Running on oeis4.)