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%I #19 Apr 06 2018 11:43:41
%S 0,1,4,13,42,137,448,1465,4790,15661,51204,167413,547362,1789617,
%T 5851208,19130705,62548430,204504021,668632204,2186113613,7147565882,
%U 23369187097,76406277968,249812682345,816770269670,2670455587581
%N Expansion of x/(1 - 4*x + 3*x^2 - 2*x^3).
%C The limiting ratio a(n+1)/a(n) is 3.269530842081143....
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (4,-3,2).
%F a(n) = 4*a(n-1) - 3*a(n-2) + 2*a(n-3), starting 0, 1, 4.
%o (PARI) Vec(x/(1-4*x+3*x^2-2*x^3)+O(x^99)) \\ _Charles R Greathouse IV_, Sep 26 2012
%Y Cf. A000045, A174631, A000931, A111285.
%K nonn,easy
%O 0,3
%A _Roger L. Bagula_, Dec 02 2010