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A144620
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Numbers k such that k and 19*k + 8 are both prime.
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2
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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
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OFFSET
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1,1
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LINKS
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EXAMPLE
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For n=5, 19*5 + 8 = 103;
for n=269, 19*269 + 8 = 5119.
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MAPLE
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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); # Emeric Deutsch, Jan 27 2009
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MATHEMATICA
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Select[Prime[Range[400]], PrimeQ[#] &&PrimeQ[19#+8] &] (* Vincenzo Librandi, Aug 30 2012 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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