A042891 Denominators of continued fraction convergents to sqrt(977).

1, 3, 4, 35, 179, 214, 393, 1393, 10144, 11537, 21681, 163304, 511593, 674897, 1186490, 6607347, 54045266, 60652613, 236003105, 14692845123, 44314538474, 59007383597, 516373607250, 2640875419847, 3157249027097

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• frac
• easy

Comments

The Hankel transform (see A001906 for definition) of this sequence forms the sequence A047656(n+1)= [1,3,27,729,59049,14348907,...] . - Philippe Deléham, Aug 29 2006

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 14753497736, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).

Crossrefs

Cf. A042890, A040945.

Programs

Mathematica

Denominator[Convergents[Sqrt[977], 40]] (* Harvey P. Dale, May 09 2012 *)

Formula

The Hankel transform (see A001906 for definition) of this sequence forms the sequence A047656(n+1)= [1,3,27,729,59049,14348907,...]. - Philippe Deléham, Aug 29 2006

a(n) = 14753497736*a(n-19) - a(n-38) for n > 37. - Vincenzo Librandi, Jan 31 2014