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A174369
Numbers k such that 12k-5, 12k+1, and 12k+7 are prime.
0
1, 3, 6, 13, 23, 31, 51, 61, 108, 121, 146, 156, 166, 178, 198, 223, 226, 233, 276, 303, 311, 376, 383, 388, 416, 426, 451, 453, 471, 506, 531, 601, 656, 726, 783, 888, 958, 986, 1081, 1098, 1213, 1266, 1276, 1311, 1326, 1518, 1536, 1601, 1623, 1696, 1791
OFFSET
1,2
EXAMPLE
a(1)=1 because 1*12-5=7, 1*12+1=13, and 1*12+7=19 are all prime.
PROG
(Magma) [n: n in [1..1000]|IsPrime(12*n-5) and IsPrime(12*n+1) and IsPrime(12*n+7)] // Vincenzo Librandi, Dec 06 2010
CROSSREFS
Sequence in context: A239987 A048134 A058397 * A308747 A022811 A295730
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Corrected by Charles R Greathouse IV, Mar 18 2010
a(18)-a(51) from Vincenzo Librandi, Mar 20 2010
STATUS
approved