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Expansion of x*(1+9*x-8*x^3)/(1-10*x^2+8*x^4).
4

%I #10 Jun 13 2015 00:55:17

%S 1,9,10,82,92,748,840,6824,7664,62256,69920,567968,637888,5181632,

%T 5819520,47272576,53092096,431272704,484364800,3934546432,4418911232,

%U 35895282688,40314193920,327476455424,367790649344,2987602292736,3355392942080,27256211283968

%N Expansion of x*(1+9*x-8*x^3)/(1-10*x^2+8*x^4).

%C It seems that this is also the first row of the spectral array W(sqrt(17)-3).

%C It also seems that, for all k>0, the first row of W(sqrt(k^2+1)-k+1) has a generating function of the form x*(1+(2*k+1)*x-2*k*x^3)/(1-(2*k+2)*x^2+2*k*x^4).

%H Colin Barker, <a href="/A249311/b249311.txt">Table of n, a(n) for n = 1..1000</a>

%H A. Fraenkel and C. Kimberling, <a href="http://dx.doi.org/10.1016/0012-365X(94)90259-3">Generalized Wythoff arrays, shuffles and interspersions</a>, Discrete Mathematics 126 (1994) 137-149.

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,10,0,-8).

%o (PARI) Vec(x*(1+9*x-8*x^3)/(1-10*x^2+8*x^4) + O(x^100))

%Y Cf. A007068 (k=1), A022165 (k=2), A249310 (k=3), A249312 (k=5), A249313 (k=6).

%K nonn,easy

%O 1,2

%A _Colin Barker_, Oct 25 2014