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%I #14 Jul 17 2023 00:22:51
%S 1,1,6,19,63,82,555,637,2466,8035,42641,50676,1866977,1917653,
%T 11455242,36283379,120305379,156588758,1059837927,1216426685,
%U 4709117982,15343780631,81428021137,96771801768,3565212884785,3661984686553,21875136317550,69287393639203
%N Denominators of continued fraction convergents to sqrt(355).
%H Vincenzo Librandi, <a href="/A041673/b041673.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, 1909618, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).
%F G.f.: -(x^22 -x^21 +6*x^20 -19*x^19 +63*x^18 -82*x^17 +555*x^16 -637*x^15 +2466*x^14 -8035*x^13 +42641*x^12 -50676*x^11 -42641*x^10 -8035*x^9 -2466*x^8 -637*x^7 -555*x^6 -82*x^5 -63*x^4 -19*x^3 -6*x^2 -x -1)/(x^24 -1909618*x^12 +1). - _Vincenzo Librandi_, Dec 22 2013
%F a(n) = 1909618*a(n-12) - a(n-24) for n>23. - _Vincenzo Librandi_, Dec 22 2013
%t Denominator/@Convergents[Sqrt[355], 40] (* _Harvey P. Dale_, May 11 2011 *)
%t CoefficientList[Series[-(x^22 - x^21 + 6 x^20 - 19 x^19 + 63 x^18 - 82 x^17 + 555 x^16 - 637 x^15 + 2466 x^14 - 8035 x^13 + 42641 x^12 - 50676 x^11 - 42641 x^10 - 8035 x^9 - 2466 x^8 - 637 x^7 - 555 x^6 - 82 x^5 - 63 x^4 - 19 x^3 - 6 x^2 - x - 1)/(x^24 - 1909618 x^12 + 1), {x, 0, 30}], x] (* _Vincenzo Librandi_, Dec 22 2013 *)
%Y Cf. A041672.
%K nonn,frac,easy
%O 0,3
%A _N. J. A. Sloane_.
%E More terms from Harvey P. Dale, May 11 2011.
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