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A105133
Numbers n such that 8n + 5 is prime.
17
0, 1, 3, 4, 6, 7, 12, 13, 18, 19, 21, 22, 24, 28, 33, 34, 36, 39, 43, 46, 48, 49, 52, 57, 63, 67, 69, 76, 81, 82, 84, 87, 88, 91, 94, 96, 99, 102, 103, 106, 109, 117, 124, 126, 127, 132, 133, 136, 138, 139, 147, 151, 153, 154, 159, 162, 171, 172, 178, 181, 186, 193, 199, 201, 202
OFFSET
1,3
LINKS
FORMULA
a(n) = (A007521(n)-5)/8. - Zak Seidov, Sep 08 2015
MAPLE
M:=500; f:=proc(n) local t1, t2; t1:=[]; for k from 0 to M do t2:=2^n*k+2^(n-1)+1; if isprime(t2) then t1:=[op(t1), k]; fi; od; t1; end; f(3);
MATHEMATICA
Select[Range[0, 300], PrimeQ[8 # + 5]&] (* Vincenzo Librandi, Jan 07 2013 *)
PROG
(Magma) [n: n in [0..500] | IsPrime(8*n+5)]; // Vincenzo Librandi, Jan 07 2013
(PARI) is(n)=isprime(8*n+5) \\ Charles R Greathouse IV, Feb 17 2017
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, based on correspondence from Marco Matosic, Apr 11 2005
STATUS
approved