The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A031840 Period of continued fraction for sqrt(n) contains exactly 72 ones. 0
 4999, 5119, 5779, 7324, 7681, 8926, 9241, 9286, 10501, 10969, 11566, 11701, 12169, 12268, 12637, 13201, 13561, 14169, 14347, 14929, 14932, 15493, 15676, 15681, 15817, 16438, 16657, 17137, 17229, 17317, 17959, 18022, 18406, 18969, 18973, 19281, 19657 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS MATHEMATICA cf72Q[n_]:=Module[{s=Sqrt[n], cf}, If[IntegerQ[s], cf={0}, cf= ContinuedFraction[ s] [[2]]]; Count[cf, 1]==72]; Select[Range[ 20000], cf72Q] (* Harvey P. Dale, Jan 14 2015 *) CROSSREFS Sequence in context: A248486 A070001 A145540 * A059667 A106767 A157367 Adjacent sequences: A031837 A031838 A031839 * A031841 A031842 A031843 KEYWORD nonn AUTHOR STATUS approved

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

Last modified December 3 13:56 EST 2022. Contains 358534 sequences. (Running on oeis4.)