%I #14 Jun 13 2015 00:49:38

%S 1,7,15,22,103,434,1839,2273,6385,46968,2072977,14557807,31188591,

%T 45746398,214174183,902443130,3823946703,4726389833,13276726369,

%U 97663474416,4310469600673,30270950679127,64852370958927,95123321638054,445345657511143,1876505951682626

%N Denominators of continued fraction convergents to sqrt(490).

%H Vincenzo Librandi, <a href="/A041935/b041935.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 (0,0,0,0,0,0,0,0,0,2079362,0,0,0,0,0,0,0,0,0,-1).

%F G.f.: -(x^18 -7*x^17 +15*x^16 -22*x^15 +103*x^14 -434*x^13 +1839*x^12 -2273*x^11 +6385*x^10 -46968*x^9 -6385*x^8 -2273*x^7 -1839*x^6 -434*x^5 -103*x^4 -22*x^3 -15*x^2 -7*x -1) / ((x^10 -1442*x^5 +1)*(x^10 +1442*x^5 +1)). - _Colin Barker_, Nov 27 2013

%F a(n) = 2079362*a(n-10) - a(n-20) for n>19. - _Vincenzo Librandi_, Dec 27 2013

%t Denominator[Convergents[Sqrt[490], 30]] (* _Vincenzo Librandi_, Dec 27 2013 *)

%Y Cf. A041934, A040467.

%K nonn,frac,easy

%O 0,2

%A _N. J. A. Sloane_.

%E More terms from _Colin Barker_, Nov 27 2013