A031790 Period of continued fraction for sqrt(n) contains exactly 22 ones.

991, 1021, 1303, 1324, 1357, 1453, 1543, 1569, 1597, 1619, 1689, 1789, 1804, 1822, 1948, 1993, 2053, 2104, 2174, 2203, 2253, 2361, 2381, 2413, 2458, 2503, 2654, 2657, 2729, 2761, 2794, 2803, 2861, 2887, 2893, 2899, 2973, 2979, 2983, 2998, 3085, 3091

Offset

1,1

Links

Table of n, a(n) for n=1..42.

Mathematica

cf22Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Count[ContinuedFraction[s][[2]], 1]]==22]; Select[Range[3500], cf22Q] (* Harvey P. Dale, Feb 18 2015 *)

Crossrefs

Sequence in context: A218401 A053393 A365598 * A137703 A255098 A155509

Adjacent sequences: A031787 A031788 A031789 * A031791 A031792 A031793

Keyword

nonn

Author

David W. Wilson

Status

approved