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%I #7 Aug 27 2021 21:16:13
%S -1,-1,2,1,11,12,39,51,122,173,359,532,1019,1551,2826,4377,7715,12092,
%T 20831,32923,55802,88725,148623,237348,394163,631511,1042058,1673569,
%U 2748395,4421964,7235895,11657859,19024826,30682685,49969655,80652340,131146283
%N a(n) = a(n-1) + 3*a(n-2) -2*a(n-3) - 2*a(n-4), where a(0) = -1, 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="/A295852/b295852.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) = -1, a(1) = -1, a(2) = 2, a(3) = 1.
%F G.f.: (-1 + 6 x^2)/(1 - x - 3 x^2 + 2 x^3 + 2 x^4).
%t LinearRecurrence[{1, 3, -2, -2}, {-1, -1, 2, 1}, 100]
%Y Cf. A001622, A000045.
%K easy,sign
%O 0,3
%A _Clark Kimberling_, Dec 01 2017
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