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A095278
Numbers k such that 4k + 3 is prime.
30
0, 1, 2, 4, 5, 7, 10, 11, 14, 16, 17, 19, 20, 25, 26, 31, 32, 34, 37, 40, 41, 44, 47, 49, 52, 55, 56, 59, 62, 65, 67, 70, 76, 77, 82, 86, 89, 91, 94, 95, 104, 107, 109, 110, 115, 116, 119, 121, 122, 124, 125, 130, 136, 140, 142, 146, 149, 151, 154, 157, 160, 161, 164
OFFSET
1,3
FORMULA
a(n) = (A002145(n) - 3)/4.
MAPLE
A095278:=n->`if`(isprime(4*n+3), n, NULL): seq(A095278(n), n=0..300); # Wesley Ivan Hurt, Jun 29 2015
MATHEMATICA
Select[Range[0, 200], PrimeQ[4#+3]&] (* Harvey P. Dale, Aug 15 2013 *)
PROG
(Magma) [n: n in [0..1000]|IsPrime(4*n+3)] // Vincenzo Librandi, Nov 16 2010
(PARI) is(n)=isprime(4*n+3) \\ Charles R Greathouse IV, Jul 01 2013
(GAP) Filtered([1..170], n->IsPrime(4*n+3)); # Muniru A Asiru, Oct 29 2018
CROSSREFS
Cf. A002145. Complement of A095277. Union of A095272 and A095273. Cf. also A005098.
Sequence in context: A050130 A039672 A014370 * A155722 A049045 A153766
KEYWORD
nonn,easy
AUTHOR
Antti Karttunen, Jun 01 2004
STATUS
approved