A031748 Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 70.

1226, 4902, 11028, 19604, 30630, 44106, 60032, 78408, 99234, 122510, 148236, 176412, 207038, 240114, 275640, 313616, 354042, 396918, 442244, 490020, 540246, 592922, 648048, 705624, 765650, 828126, 893052, 960428, 1030254, 1102530

Offset

1,1

Comments

a(n) = 1225n^2 + n for n < 73, but a(73) = 6355512. - Charles R Greathouse IV, Aug 04 2017

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Mathematica

ltcf70Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Min[ ContinuedFraction[ s] [[2]]]]==70]; Select[Range[1200000], ltcf70Q] (* Harvey P. Dale, Jun 14 2015 *)

Crossrefs

Sequence in context: A151657 A218273 A046177 * A031658 A031533 A031713

Adjacent sequences: A031745 A031746 A031747 * A031749 A031750 A031751

Keyword

nonn

Author

David W. Wilson

Status

approved