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%I #7 Aug 27 2021 21:19:26
%S 0,-1,1,1,6,9,23,36,75,119,226,361,651,1044,1823,2931,5010,8069,13591,
%T 21916,36531,58959,97538,157521,259155,418724,686071,1108891,1811346,
%U 2928429,4772543,7717356,12555435,20305559,32992066,53363161,86617371,140111604
%N a(n) = a(n-1) + 3*a(n-2) -2*a(n-3) - 2*a(n-4), where a(0) = 0, a(1) = -1, a(2) = 1, 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="/A295726/b295726.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) = 0, a(1) = -1, a(2) = 1, a(3) = 1.
%F G.f.: (-x + 2 x^2 + 3 x^3)/(1 - x - 3 x^2 + 2 x^3 + 2 x^4).
%t LinearRecurrence[{1, 3, -2, -2}, {0, -1, 1, 1}, 100]
%Y Cf. A001622, A000045, A005672.
%K easy,sign
%O 0,5
%A _Clark Kimberling_, Nov 29 2017
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