OFFSET
1,1
LINKS
Bernhard Helmes, Prime sieving on the polynomial f(n)=4n^2+1.
MATHEMATICA
d = 10; l = 0; p = 4; c = {}; a = {}; Do[k = p x^2 + 1; b = Divisors[k]; Do[If[PrimeQ[b[[n]]], AppendTo[a, b[[n]]]], {n, 1, Length[b]}]; If[x == d, a = Union[a]; l = Length[a]; d = 10 d; Print[l]; AppendTo[c, l]], {x, 1, 10000}]; c (*Artur Jasinski*)
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski & Bernhard Helmes (bhelmes(AT)gmx.de), Sep 22 2008
EXTENSIONS
Fixed broken link, corrected and extended to agree with website. - Ray Chandler, Jun 30 2015
STATUS
approved