A031798 Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 30 ones.

1279, 1366, 1684, 1941, 2181, 2206, 2326, 2396, 2446, 2551, 2569, 2707, 2851, 3022, 3397, 3446, 3559, 3628, 3644, 3734, 3766, 3823, 3849, 3851, 4051, 4132, 4169, 4222, 4249, 4393, 4432, 4436, 4617, 4639, 4713, 4834, 4871, 4915, 4937, 5006, 5029, 5074

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Mathematica

q[k_] := Module[{c = ContinuedFraction[Sqrt[k]]}, Length[c] == 2 && Count[c[[2]], 1] == 30]; Select[Range[6000], q] (* Amiram Eldar, Aug 11 2025 *)

Crossrefs

Sequence in context: A202643 A237407 A251097 * A293923 A251890 A251889

Adjacent sequences: A031795 A031796 A031797 * A031799 A031800 A031801

Keyword

nonn

Author

David W. Wilson

Status

approved