A020414 Numbers k such that the continued fraction for sqrt(k) has period 75.

3217, 3313, 7237, 9209, 9466, 10249, 10765, 11521, 11785, 12442, 12757, 13709, 13757, 14125, 15577, 16897, 19421, 19577, 19786, 19913, 21562, 22277, 22837, 29765, 31517, 31741, 32458, 32489, 33202, 33893, 34165, 35153, 36506, 41845, 42314, 42802

Offset

1,1

Links

Table of n, a(n) for n=1..36.

Mathematica

cf75Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Length[ ContinuedFraction[ s][[2]]]]==75]; Select[Range[43000], cf75Q] (* Harvey P. Dale, Apr 17 2020 *)

Crossrefs

Cf. A003285.

Sequence in context: A091329 A261241 A345772 * A202612 A376136 A295474

Adjacent sequences: A020411 A020412 A020413 * A020415 A020416 A020417

Keyword

nonn

Author

David W. Wilson

Status

approved