login
A031813
Period of continued fraction for sqrt(n) contains exactly 45 ones.
0
20875, 25559, 25591, 32875, 39447, 50879, 51847, 57955, 62419, 70599, 70871, 75947, 77087, 78055, 82711, 84639, 86995, 95839, 96472, 98059, 98651, 100951, 103000, 105419, 105671, 107271, 108824, 112144, 117107, 119755, 123163, 126355, 128547
OFFSET
1,1
MATHEMATICA
cf45Q[n_]:=Module[{c=Sqrt[n]}, !IntegerQ[c]&&Count[ContinuedFraction[ c] [[2]], 1]==45]; Select[Range[150000], cf45Q] (* Harvey P. Dale, Dec 24 2012 *)
CROSSREFS
Sequence in context: A207794 A368426 A256840 * A043654 A188104 A278903
KEYWORD
nonn
STATUS
approved