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%I #19 Mar 03 2024 19:43:04
%S 1,4,5,9,77,86,163,738,26731,107662,134393,242055,2070833,2312888,
%T 4383721,19847772,718903513,2895461824,3614365337,6509827161,
%U 55692982625,62202809786,117895792411,533785979430,19334191051891,77870550186994,97204741238885
%N Denominators of continued fraction convergents to sqrt(332).
%H Vincenzo Librandi, <a href="/A041627/b041627.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 26894, 0, 0, 0, 0, 0, 0, 0, -1).
%F G.f.: -(x^14 -4*x^13 +5*x^12 -9*x^11 +77*x^10 -86*x^9 +163*x^8 -738*x^7 -163*x^6 -86*x^5 -77*x^4 -9*x^3 -5*x^2 -4*x -1) / ((x^8 -164*x^4 +1)*(x^8 +164*x^4 +1)). - _Colin Barker_, Nov 20 2013
%F a(n) = 26894*a(n-8) - a(n-16) for n>15. - _Vincenzo Librandi_, Dec 22 2013
%t Denominator[Convergents[Sqrt[332], 30]] (* _Vincenzo Librandi_, Dec 22 2013 *)
%t LinearRecurrence[{0,0,0,0,0,0,0,26894,0,0,0,0,0,0,0,-1},{1,4,5,9,77,86,163,738,26731,107662,134393,242055,2070833,2312888,4383721,19847772},30] (* _Harvey P. Dale_, Mar 03 2024 *)
%o (Magma) I:=[1,4,5,9,77,86,163,738,26731,107662,134393, 242055,2070833,2312888,4383721,19847772]; [n le 16 select I[n] else 26894*Self(n-8)-Self(n-16): n in [1..40]]; // _Vincenzo Librandi_, Dec 22 2013
%Y Cf. A041626, A040313.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Nov 20 2013