login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A031859 Period of continued fraction for sqrt(n) contains exactly 91 ones. 0
64051, 75799, 76639, 85783, 129299, 132487, 146467, 148264, 151859, 162131, 162511, 192131, 214927, 223343, 224779, 224899, 250931, 251395, 262456, 273607, 289931, 292811, 316611, 318491, 331255, 343864, 345043, 346019, 347459, 353995 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..30.

MATHEMATICA

cf91Q[n_]:=Module[{sr=Sqrt[n], p}, p=If[IntegerQ[sr], 1, Count[ ContinuedFraction[ sr][[2]], 1]]; p==91]; Select[Range[400000], cf91Q] (* Harvey P. Dale, Jan 22 2014 *)

CROSSREFS

Sequence in context: A250823 A054738 A250617 * A182811 A236702 A224827

Adjacent sequences:  A031856 A031857 A031858 * A031860 A031861 A031862

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 26 06:11 EDT 2020. Contains 338027 sequences. (Running on oeis4.)