OFFSET
1,2
MATHEMATICA
ks[n_]:=Module[{k=1}, If[IntegerQ[Sqrt[n]], 0, While[!IntegerQ[ Sqrt[ n*k^2+n*k+1]], k++]; k]]; Array[ks, 80] (* Harvey P. Dale, Jul 18 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Pierre CAMI, Mar 30 2005
STATUS
approved