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%I #14 Sep 08 2022 08:44:55
%S 1,2,3,5,28,33,457,490,2907,3397,6304,16005,934594,1885193,2819787,
%T 4704980,26344687,31049667,429990358,461040025,2735190483,3196230508,
%U 5931420991,15059072490,879357625411,1773774323312,2653131948723,4426906272035,24787663308898
%N Denominators of continued fraction convergents to sqrt(864).
%H Vincenzo Librandi, <a href="/A042669/b042669.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 (0,0,0,0,0,0,0,0,0,0,0,940898,0,0,0,0,0,0,0,0,0,0,0,-1).
%F G.f.: -(x^22 -2*x^21 +3*x^20 -5*x^19 +28*x^18 -33*x^17 +457*x^16 -490*x^15 +2907*x^14 -3397*x^13 +6304*x^12 -16005*x^11 -6304*x^10 -3397*x^9 -2907*x^8 -490*x^7 -457*x^6 -33*x^5 -28*x^4 -5*x^3 -3*x^2 -2*x -1) / ((x^4 -6*x^3 +13*x^2 -6*x +1)*(x^4 -10*x^2 +1)*(x^4 +10*x^2 +1)*(x^4 +6*x^3 +13*x^2 +6*x +1)*(x^8 +10*x^6 +99*x^4 +10*x^2 +1)). - _Colin Barker_, Dec 20 2013
%F a(n) = 940898*a(n-12) - a(n-24) for n>23. - _Vincenzo Librandi_, Dec 20 2013
%t Denominator[Convergents[Sqrt[864], 30]] (* _Vincenzo Librandi_, Dec 20 2013 *)
%o (Magma) I:=[1,2,3,5,28,33,457,490,2907,3397,6304,16005, 934594,1885193,2819787,4704980,26344687,31049667, 429990358,461040025,2735190483,3196230508,5931420991, 15059072490]; [n le 24 select I[n] else 940898*Self(n-12)-Self(n-24): n in [1..40]]; // _Vincenzo Librandi_, Dec 20 2013
%Y Cf. A042668, A040834.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Dec 20 2013
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