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%I #6 Oct 03 2015 11:36:15
%S 1,5,25,115,500,2092,8512,33910,132892,514079,1968021,7470434,
%T 28160354,105542777,393672627,1462503264,5414896000,19991387639,
%U 73628208598,270614786791,992880076249,3637400475618,13308475404934,48639360355243,177597694845849
%N G.f.: (1-x)^9/((1-5*x+6*x^2-4*x^3+x^4)*(-1+4*x-3*x^2+x^3)*(1-3*x+x^2)*(-1+2*x)).
%D A. Burstein and T. Mansour, Words restricted by 3-letter ..., Annals. Combin., 7 (2003), 1-14; see Th. 3.6, case k=5.
%H A. Burstein and T. Mansour, <a href="http://arXiv.org/abs/math.CO/0112281">Words restricted by 3-letter ...</a>.
%H <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (14, -81, 254, -481, 588, -485, 270, -98, 21, -2).
%t CoefficientList[Series[(1-x)^9/((1-5x+6x^2-4x^3+x^4)(-1+4x-3x^2+x^3)(1-3x+x^2)(-1+2x)),{x,0,30}],x] (* or *) LinearRecurrence[{14,-81,254,-481,588,-485,270,-98,21,-2},{1,5,25,115,500,2092,8512,33910,132892,514079},30] (* _Harvey P. Dale_, Oct 03 2015 *)
%Y Cf. A061667, A089883, A089932.
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Jan 18 2004
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