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%I #19 Sep 08 2022 08:44:55
%S 1,1,2,3,20,23,43,66,3343,3409,6752,10161,67718,77879,145597,223476,
%T 11319397,11542873,22862270,34405143,229293128,263698271,492991399,
%U 756689670,38327474899,39084164569,77411639468,116495804037,776386463690,892882267727
%N Denominators of continued fraction convergents to sqrt(658).
%H Vincenzo Librandi, <a href="/A042265/b042265.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, 3386, 0, 0, 0, 0, 0, 0, 0, -1).
%F G.f.: -(x^2-x-1)*(x^4+3*x^2+1)*(x^8+22*x^4+1) / (x^16-3386*x^8+1). - _Colin Barker_, Dec 06 2013
%F a(n) = 3386*a(n-8) - a(n-16) for n>15. - _Vincenzo Librandi_, Jan 19 2014
%p convert(sqrt(658),confrac,30,cvgts): denom(cvgts); # _Wesley Ivan Hurt_, Dec 07 2013
%t Denominator[Convergents[Sqrt[658], 30]] (* _Vincenzo Librandi_, Jan 19 2014 *)
%o (Magma) I:=[1,1,2,3,20,23,43,66,3343,3409,6752,10161, 67718,77879,145597,223476]; [n le 16 select I[n] else 3386*Self(n-8)-Self(n-16): n in [1..40]]; // _Vincenzo Librandi_, Jan 19 2014
%Y Cf. A042264, A040632.
%K nonn,frac,easy
%O 0,3
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Dec 06 2013