%I #20 Mar 15 2024 10:06:21
%S 1,1,1,1,2,3,5,7,10,14,21,31,46,67,98,143,210,308,452,662,970,1421,
%T 2083,3053,4475,6558,9611,14085,20643,30254,44340,64983,95237,139576,
%U 204559,299796,439373,643932,943728,1383100,2027032,2970760,4353861,6380893
%N Expansion of 1/(1-x-x^4-x^6).
%C Number of compositions of n into parts 1, 4, and 6. [_Joerg Arndt_, Sep 03 2013]
%H Vincenzo Librandi, <a href="/A120446/b120446.txt">Table of n, a(n) for n = 0..1000</a>
%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).
%t CoefficientList[Series[1 / (1 - x - x^4 - x^6), {x, 0, 50}], x] (* _Vincenzo Librandi_, Sep 03 2013 *)
%t LinearRecurrence[{1,0,0,1,0,1},{1,1,1,1,2,3},50] (* _Harvey P. Dale_, Feb 11 2020 *)
%o (Magma) I:=[1,1,1,1,2,3]; [n le 6 select I[n] else Self(n-1)+Self(n-4)+Self(n-6): n in [1..50]]; // _Vincenzo Librandi_, Sep 03 2013
%K easy,nonn,changed
%O 0,5
%A _Jon E. Schoenfield_, Aug 27 2006
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