login
Denominators of continued fraction convergents to sqrt(978).
2

%I #18 Jun 26 2022 23:51:11

%S 1,3,4,7,11,337,348,685,1033,3784,235641,710707,946348,1657055,

%T 2603403,79759145,82362548,162121693,244484241,895574416,55770098033,

%U 168205868515,223975966548,392181835063,616157801611,18876915883393,19493073685004,38369989568397

%N Denominators of continued fraction convergents to sqrt(978).

%H Vincenzo Librandi, <a href="/A042893/b042893.txt">Table of n, a(n) for n = 0..200</a>

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,236674,0,0,0,0,0,0,0,0,0,-1).

%F 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

%F a(n) = 236674*a(n-10) - a(n-20) for n > 19. - _Vincenzo Librandi_, Feb 01 2014

%t Denominator[Convergents[Sqrt[978], 30]] (* _Vincenzo Librandi_, Feb 01 2014 *)

%Y Cf. A042892, A040946.

%K nonn,frac,easy

%O 0,2

%A _N. J. A. Sloane_

%E More terms from _Colin Barker_, Dec 25 2013