A155133 Numbers n >= 0 such that 5n^2+4n+1 is prime.

2, 4, 8, 10, 12, 18, 20, 30, 40, 44, 52, 54, 58, 62, 70, 72, 80, 84, 92, 98, 104, 114, 120, 124, 130, 132, 138, 140, 158, 168, 172, 174, 182, 188, 192, 194, 212, 214, 222, 238, 254, 262, 268, 274, 280, 288, 290, 294, 300, 302, 304, 314, 318, 328, 338, 342, 348

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Example

For n=2, p=29; n=30, p=421; n=44, p=9857.

Mathematica

Select[Range[0, 400], PrimeQ[5#^2+4#+1]&] (* Vincenzo Librandi, Sep 24 2012 *)

Prog

(Magma) [n: n in [0..450] | IsPrime(5*n^2+4*n+1)]; Vincenzo Librandi, Sep 24 2012

Crossrefs

Sequence in context: A032368 A134533 A089953 * A331669 A154788 A219617

Adjacent sequences: A155130 A155131 A155132 * A155134 A155135 A155136

Keyword

nonn,easy

Author

Vincenzo Librandi, Jan 20 2009

Status

approved