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A124855
Numbers k such that 3k + 4 and 4k + 3 are primes.
1
1, 5, 11, 19, 25, 31, 41, 49, 59, 65, 89, 91, 109, 115, 121, 125, 151, 161, 179, 181, 205, 209, 229, 241, 245, 275, 305, 329, 331, 349, 355, 361, 371, 389, 415, 439, 509, 515, 521, 535, 551, 595, 599, 625, 661, 665, 671, 719, 725, 749, 755, 769, 779, 791, 839
OFFSET
1,2
MATHEMATICA
Select[Range[850], PrimeQ[3# + 4] && PrimeQ[4# + 3] &] (* Ray Chandler, May 11 2007 *)
PROG
(Magma) [n: n in [0..1000] | IsPrime(3*n+4) and IsPrime(4*n+3)] // Vincenzo Librandi, Mar 26 2010
CROSSREFS
Intersection of A034936 and A095278. Prime terms are in A106068.
Sequence in context: A117089 A356140 A114269 * A286690 A363637 A190756
KEYWORD
nonn
AUTHOR
Zak Seidov, Nov 10 2006
STATUS
approved