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A123979
Numbers k such that 12*k+1, 12*k+5 and 12*k+7 are primes.
2
1, 3, 8, 16, 23, 38, 51, 71, 73, 108, 141, 156, 166, 178, 198, 233, 271, 288, 346, 376, 451, 453, 471, 478, 646, 656, 773, 778, 786, 871, 926, 1003, 1013, 1031, 1156, 1213, 1311, 1338, 1543, 1576, 1618, 1696, 1751, 1776, 1793, 1846, 1856, 1921, 1933, 1963
OFFSET
1,2
LINKS
MAPLE
a:=proc(n) if isprime(12*n+1)=true and isprime(12*n+5)=true and isprime(12*n+7)=true then n else fi end: seq(a(n), n=1..2800); # Emeric Deutsch, Nov 06 2006
MATHEMATICA
Select[Range[2000], And @@ PrimeQ /@ ({1, 5, 7} + 12#) &] (* Ray Chandler, Nov 05 2006 *)
CROSSREFS
Cf. A110801.
Sequence in context: A275239 A190450 A188012 * A013583 A122794 A225268
KEYWORD
nonn
AUTHOR
Artur Jasinski, Oct 30 2006
EXTENSIONS
Extended by Ray Chandler, Nov 05 2006
More terms from Emeric Deutsch, Nov 06 2006
STATUS
approved