A042169 - OEIS

%I #19 May 19 2019 02:11:14

%S 1,1,3,28,31,59,385,444,829,7905,16639,24544,1194751,1219295,3633341,

%T 33919364,37552705,71472069,466385119,537857188,1004242307,9576037951,

%U 20156318209,29732356160,1447309413889,1477041770049,4401392953987,41089578355932

%N Denominators of continued fraction convergents to sqrt(609).

%H Vincenzo Librandi, <a href="/A042169/b042169.txt">Table of n, a(n) for n = 0..200</a>

%H <a href="/index/Rec#order_24">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1211390, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

%F G.f.: -(x^22 - x^21 + 3*x^20 - 28*x^19 + 31*x^18 - 59*x^17 + 385*x^16 - 444*x^15 + 829*x^14 - 7905*x^13 + 16639*x^12 - 24544*x^11 - 16639*x^10 - 7905*x^9 - 829*x^8 - 444*x^7 - 385*x^6 - 59*x^5 - 31*x^4 - 28*x^3 - 3*x^2 - x - 1) / (x^24 - 1211390*x^12 + 1). - _Colin Barker_, Dec 03 2013

%t Denominator[Convergents[Sqrt[609], 30]] (* _Vincenzo Librandi_, Jan 16 2014 *)

%Y Cf. A042168, A040584.

%K nonn,frac,easy

%O 0,3

%A _N. J. A. Sloane_

%E More terms from _Colin Barker_, Dec 03 2013