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A154651
Numbers n such that 991*n^2+1 is a prime.
2
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
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
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jan 18 2009
STATUS
approved