%I
%S 27,28,1539,1567,86157,87724,4823253,4910977,270016011,274926988,
%T 15116073363,15391000351,846230092317,861621092668,47373769096389,
%U 48235390189057,2652084839305467,2700320229494524
%N Numerators of continued fraction convergents to sqrt(783).
%H Vincenzo Librandi, <a href="/A042510/b042510.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,56,0,1).
%F G.f.: (27 + 28*x + 27*x^2  x^3)/(1  56*x^2 + x^4).  _Vincenzo Librandi_, Nov 26 2013
%F a(n) = 56*a(n2)  a(n4).  _Vincenzo Librandi_, Nov 26 2013
%t Numerator[Convergents[Sqrt[783], 30]] (* or *) CoefficientList[Series[(27 + 28 x + 27 x^2  x^3)/(1  56 x^2 + x^4), {x, 0, 30}], x] (* _Vincenzo Librandi_, Nov 25 2013 *)
%t LinearRecurrence[{0,56,0,1},{27,28,1539,1567},30] (* _Harvey P. Dale_, Apr 28 2016 *)
%o (MAGMA) I:=[27, 28, 1539, 1567]; [n le 4 select I[n] else 56*Self(n2)Self(n4): n in [1..30]]; // _Vincenzo Librandi_, Nov 26 2013
%Y Cf. A042511.
%K nonn,cofr,frac,easy
%O 0,1
%A _N. J. A. Sloane_
