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%I #17 Jun 13 2015 00:49:21
%S 7,15,22,147,169,485,6959,14403,21362,142575,163937,470449,6750223,
%T 13970895,20721118,138297603,159018721,456335045,6547709351,
%U 13551753747,20099463098,134148532335,154247995433
%N Numerators of continued fraction convergents to sqrt(54).
%H Vincenzo Librandi, <a href="/A041092/b041092.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 (0,0,0,0,0,970,0,0,0,0,0,-1).
%F a(n) = 970*a(n-6)-a(n-12). G.f.: -(x^11-7*x^10+15*x^9-22*x^8+147*x^7-169*x^6-485*x^5-169*x^4-147*x^3-22*x^2-15*x-7)/((x^4-10*x^2+1)*(x^8+10*x^6+99*x^4+10*x^2+1)). [_Colin Barker_, Jul 18 2012]
%t Numerator[Convergents[Sqrt[54],30]] (* _Harvey P. Dale_, Jul 18 2013 *)
%t CoefficientList[Series[- (x^11 - 7 x^10 + 15 x^9 - 22 x^8 + 147 x^7 - 169 x^6 - 485 x^5 - 169 x^4 - 147 x^3 - 22 x^2 - 15 x - 7)/((x^4 - 10 x^2 + 1) (x^8 + 10 x^6 + 99 x^4 + 10 x^2 + 1)), {x, 0, 30}], x] (* _Vincenzo Librandi_, Oct 25 2013 *)
%Y Cf. A010507, A041093.
%K nonn,cofr,frac,easy
%O 0,1
%A _N. J. A. Sloane_.