%I #7 Aug 27 2021 21:16:03
%S -2,-1,2,1,13,14,47,61,148,209,437,646,1243,1889,3452,5341,9433,14774,
%T 25487,40261,68308,108569,181997,290566,482803,773369,1276652,2050021,
%U 3367633,5417654,8867207,14284861,23315908,37600769,61244357,98845126,160744843
%N a(n) = a(n-1) + 3*a(n-2) -2*a(n-3) - 2*a(n-4), where a(0) = -2, a(1) = -1, a(2) = 2, a(3) = 1.
%C a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622), so that a( ) has the growth rate of the Fibonacci numbers (A000045).
%H Clark Kimberling, <a href="/A295853/b295853.txt">Table of n, a(n) for n = 0..2000</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (1, 3, -2, -2)
%F a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = -2, a(1) = -1, a(2) = 2, a(3) = 1.
%F G.f.: (-2 + x + 9 x^2 - 2 x^3)/(1 - x - 3 x^2 + 2 x^3 + 2 x^4).
%t LinearRecurrence[{1, 3, -2, -2}, {-2, -1, 2, 1}, 100]
%Y Cf. A001622, A000045.
%K easy,sign
%O 0,1
%A _Clark Kimberling_, Dec 01 2017
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