|
|
A031781
|
|
Period of continued fraction for sqrt(n) contains exactly 13 ones.
|
|
1
|
|
|
1219, 1591, 2071, 2107, 3375, 3655, 4175, 4399, 4671, 4847, 4888, 4891, 5319, 5395, 6208, 7067, 7144, 7515, 11800, 12328, 12875, 12947, 13144, 13199, 13511, 14027, 14319, 15151, 15272, 16120, 16403, 17331, 17759, 17936, 18483, 19327, 19527, 19691
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
LINKS
|
|
|
MATHEMATICA
|
cf13Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Count[ ContinuedFraction[ s][[2]], 1]]==13]; Select[Range[20000], cf13Q] (* Harvey P. Dale, Jun 16 2017 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|