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A124486
Numbers k such that 2*k-1, 4*k-1 and 6*k-1 are primes.
2
2, 3, 12, 15, 42, 45, 87, 117, 120, 147, 210, 330, 477, 507, 612, 705, 780, 792, 945, 1002, 1065, 1170, 1275, 1347, 1470, 1680, 1695, 1797, 1902, 2175, 2187, 2205, 2460, 2472, 2667, 3057, 3087, 4047, 4137, 4257, 4530, 4740, 4770, 5082, 5157, 5295, 5775
OFFSET
1,1
LINKS
MATHEMATICA
Select[Range[6000], And @@ PrimeQ /@ ({2, 4, 6}*# - 1) &] (* Ray Chandler, Nov 21 2006 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Nov 04 2006
EXTENSIONS
Extended by Ray Chandler, Nov 21 2006
STATUS
approved