A031811 - OEIS

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A031811

Period of continued fraction for sqrt(n) contains exactly 43 ones.

15871, 30847, 31171, 41839, 42631, 54859, 62923, 65591, 66187, 68056, 68944, 69299, 70855, 77875, 80999, 83931, 92491, 95875, 96695, 97507, 100264, 106856, 109336, 109855, 110707, 115216, 115519, 122200, 124415, 124931, 132995, 135143, 139551 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	LINKS	`Table of n, a(n) for n=1..33.`
	MATHEMATICA	`cf43Q[n_]:=Module[{sn=Sqrt[n]}, !IntegerQ[sn]&&Count[ ContinuedFraction[ sn][[2]], 1]==43]; Select[Range[140000], cf43Q] (* Harvey P. Dale, Apr 25 2012 *)`
	CROSSREFS	`Sequence in context: A184612 A277350 A101320 * A234318 A174596 A237071` `Adjacent sequences: A031808 A031809 A031810 * A031812 A031813 A031814`
	KEYWORD	`nonn`
	AUTHOR	`David W. Wilson`
	STATUS	`approved`

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Last modified December 6 22:36 EST 2023. Contains 367616 sequences. (Running on oeis4.)