A094896 If 4*n+1 is prime and 4*n+3 is not prime then a(n)=4*n+1, else a(n)=0.

0, 0, 0, 13, 0, 0, 0, 0, 0, 37, 0, 0, 0, 53, 0, 61, 0, 0, 73, 0, 0, 0, 89, 0, 97, 0, 0, 109, 113, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 157, 0, 0, 0, 173, 0, 181, 0, 0, 193, 0, 0, 0, 0, 0, 0, 0, 0, 229, 233, 0, 241, 0, 0, 0, 257, 0, 0, 0, 0, 277, 0, 0, 0, 293, 0, 0, 0, 0, 313, 317, 0, 0, 0, 0, 337, 0, 0

Offset: 0

Author

Roger L. Bagula, Jun 14 2004

Keywords

• nonn

Crossrefs

Cf. A005098, A095277, A094897.

Programs

Magma

[IsPrime(4*n+1) and not IsPrime(4*n+3) select 4*n+1 else 0:n in [0..86]]; // Marius A. Burtea, Nov 15 2019

Maple

A094896 := proc(n)
    if isprime(4*n+1) and not isprime(4*n+3) then
        4*n+1;
    else
        0;
    end if;
end proc:
seq(A094896(n),n=0..86) ; # R. J. Mathar, Nov 15 2019

Mathematica

a=Table[If[PrimeQ[4*n+1]==True&&PrimeQ[4*n+3]==False, 4*n+1, 0], {n, 0, 200}]