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A042893 Denominators of continued fraction convergents to sqrt(978). 2
1, 3, 4, 7, 11, 337, 348, 685, 1033, 3784, 235641, 710707, 946348, 1657055, 2603403, 79759145, 82362548, 162121693, 244484241, 895574416, 55770098033, 168205868515, 223975966548, 392181835063, 616157801611, 18876915883393, 19493073685004, 38369989568397 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,236674,0,0,0,0,0,0,0,0,0,-1).

FORMULA

G.f.: -(x^18 -3*x^17 +4*x^16 -7*x^15 +11*x^14 -337*x^13 +348*x^12 -685*x^11 +1033*x^10 -3784*x^9 -1033*x^8 -685*x^7 -348*x^6 -337*x^5 -11*x^4 -7*x^3 -4*x^2 -3*x -1) / (x^20 -236674*x^10 +1). - Colin Barker, Dec 25 2013

a(n) = 236674*a(n-10) - a(n-20) for n>19. - Vincenzo Librandi, Feb 01 2014

MATHEMATICA

Denominator[Convergents[Sqrt[978], 30]] (* Vincenzo Librandi, Feb 01 2014 *)

CROSSREFS

Cf. A042892, A040946.

Sequence in context: A291853 A041153 A041781 * A132111 A164831 A085188

Adjacent sequences:  A042890 A042891 A042892 * A042894 A042895 A042896

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Dec 25 2013

STATUS

approved

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Last modified March 21 22:19 EDT 2019. Contains 321382 sequences. (Running on oeis4.)