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%I #23 Sep 08 2022 08:45:51
%S 1,1,1,1,2,3,3,3,4,6,7,7,8,11,14,15,16,20,26,30,32,37,47,57,63,70,85,
%T 105,121,134,156,191,227,256,291,348,419,484,548,640,768,904,1033,
%U 1189,1409,1673,1938,2223,2599,3083,3612,4162,4823,5683,6696,7775,8986
%N Expansion of 1/(1 - x - x^4 + x^6).
%C Low limiting ratio in 100th iteration near 1.16663.
%C The polynomial is interesting for the puzzling low ratio and the Salem like root structure with two complex roots outside the unit circle.
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,1,0,-1).
%F a(n) = a(n-1) + a(n-4) + a(n-6). - _Franck Maminirina Ramaharo_, Oct 31 2018
%t CoefficientList[Series[1/(1 - x - x^4 + x^6), {x, 0, 60}], x]
%o (PARI) x='x+O('x^50); Vec(1/(1 - x - x^4 + x^6)) \\ _G. C. Greubel_, Nov 03 2018
%o (Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/(1 - x - x^4 + x^6))); // _G. C. Greubel_, Nov 03 2018
%Y Cf. A029826, A117791, A143419, A143438, A143472, A143619, A143644, A147663, A173908, A173911, A173924, A173925, A175740, A175772, A175773, A175782, A181600, A204631, A225391, A225393, A225394, A225482, A225499.
%K nonn,easy
%O 0,5
%A _Roger L. Bagula_, Nov 28 2010