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Denominators of continued fraction convergents to sqrt(30).
3

%I #35 Aug 11 2024 09:55:13

%S 1,2,21,44,461,966,10121,21208,222201,465610,4878301,10222212,

%T 107100421,224423054,2351330961,4927084976,51622180721,108171446418,

%U 1133336644901,2374844736220,24881784007101

%N Denominators of continued fraction convergents to sqrt(30).

%H Vincenzo Librandi, <a href="/A041049/b041049.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 (0,22,0,-1).

%F G.f.: (1+2*x-x^2)/(1-22*x^2+x^4). [_Colin Barker_, Jan 02 2012]

%t Table[Denominator[FromContinuedFraction[ContinuedFraction[Sqrt[30], n]]],{n, 1, 50}] (* _Vladimir Joseph Stephan Orlovsky_, Mar 18 2011 *)

%t Denominator[Convergents[Sqrt[30], 20]] (* _Vincenzo Librandi_, Oct 23 2013 *)

%Y Cf. A010485, A040024, A041048 (numerators).

%K nonn,cofr,frac,easy

%O 0,2

%A _N. J. A. Sloane_