A293028 Period of the continued fraction for sqrt(5^(2n+1)).

1, 5, 31, 153, 745, 3779, 19011, 95121, 475251, 2375759, 11880177, 59406541, 297033919, 1485165459, 7425797777, 37129022423

Offset

0,2

Links

Table of n, a(n) for n=0..15.

Formula

a(n) = A003285(A013710(n)). - Michel Marcus, Sep 25 2019

Mathematica

Table[Length[Last[ContinuedFraction[Sqrt[5^(2n+1)] ]]], {n, 0, 11}] (* Metin Sariyar, Sep 25 2019 *)

Crossrefs

Cf. A003285, A013710, A064932.

Sequence in context: A293716 A294692 A047109 * A165610 A092496 A045904

Adjacent sequences: A293025 A293026 A293027 * A293029 A293030 A293031

Keyword

nonn,more

Author

A.H.M. Smeets, Sep 28 2017

Extensions

a(11)-a(13) from Daniel Suteu, Jan 24 2019

Better name from Daniel Suteu, Jan 24 2019

a(14)-a(15) from Chai Wah Wu, Sep 25 2019

Status

approved