A042025 Denominators of continued fraction convergents to sqrt(536).

1, 6, 7, 13, 33, 178, 389, 567, 956, 6303, 290894, 1751667, 2042561, 3794228, 9631017, 51949313, 113529643, 165478956, 279008599, 1839530550, 84897413899, 511224013944, 596121427843, 1107345441787, 2810812311417, 15161406998872, 33133626309161

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,291850,0,0,0,0,0,0,0,0,0,-1).

Formula

G.f.: -(x^18 -6*x^17 +7*x^16 -13*x^15 +33*x^14 -178*x^13 +389*x^12 -567*x^11 +956*x^10 -6303*x^9 -956*x^8 -567*x^7 -389*x^6 -178*x^5 -33*x^4 -13*x^3 -7*x^2 -6*x -1) / (x^20 -291850*x^10 +1). - Colin Barker, Nov 29 2013

a(n) = 291850*a(n-10) - a(n-20) for n>19. - Vincenzo Librandi, Jan 12 2014

Mathematica

Denominator[Convergents[Sqrt[536], 30]] (* Vincenzo Librandi, Jan 12 2014 *)

Crossrefs

Cf. A042024, A040512.

Sequence in context: A020689 A128844 A128850 * A041072 A154741 A041999

Adjacent sequences: A042022 A042023 A042024 * A042026 A042027 A042028

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Nov 29 2013

Status

approved