A154651 Numbers n such that 991*n^2+1 is a prime.

6, 46, 60, 70, 74, 114, 116, 160, 174, 200, 234, 254, 256, 260, 264, 294, 296, 304, 306, 326, 360, 370, 376, 380, 390, 406, 416, 420, 460, 474, 500, 506, 516, 534, 550, 564, 580, 620, 630, 634, 644, 664, 684, 694, 706, 710, 740, 744, 750, 770, 786, 800, 824

Offset

1,1

Comments

991*n^2+1 is a square for n=12055735790331359447442538767.

Links

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

Example

for n=6, 991*n^2+1=35677; n=46, 991*n^2+1=2090957.

Mathematica

Select[Range[0, 1000], PrimeQ[991#^2+1]&] (* Vincenzo Librandi, Sep 24 2012 *)

Prog

(Magma) [n: n in [0..900] | IsPrime(991*n^2+1)]; Vincenzo Librandi, Sep 24 2012

Crossrefs

Sequence in context: A086721 A145002 A043076 * A327935 A079910 A103768

Adjacent sequences: A154648 A154649 A154650 * A154652 A154653 A154654

Keyword

nonn,easy

Author

Vincenzo Librandi, Jan 18 2009

Status

approved