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%I #27 Feb 09 2018 12:48:20
%S 1,1,1,2,8,4,3,27,9,4,64,16,5,125,25,6,216,36,7,343,49,8,512,64,9,729,
%T 81,10,1000,100,11,1331,121,12,1728,144,13,2197,169,14,2744,196,15,
%U 3375,225,16,4096,256,17,4913,289,18,5832,324,19,6859,361,20,8000,400
%N n followed by n^3 followed by n^2.
%H Iain Fox, <a href="/A109594/b109594.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Colin Barker)
%H <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,4,0,0,-6,0,0,4,0,0,-1).
%F From _Colin Barker_, Dec 02 2015: (Start)
%F a(n) = 4*a(n-3) - 6*a(n-6) + 4*a(n-9) - a(n-12) for n > 12.
%F G.f.: x*(1+x+x^2-2*x^3+4*x^4+x^6+x^7-x^8) / ((1-x)^4*(1+x+x^2)^4).
%F (End)
%F a(n) = floor((n+2)/3)^((3*(n mod 3)^2-5*(n mod 3)+4)/2). - _Luce ETIENNE_, Dec 17 2017
%p map(t -> (t,t^3,t^2), [$1..100]); # _Robert Israel_, Dec 17 2017
%t Flatten[Table[{n,n^3,n^2},{n,20}]] (* _Harvey P. Dale_, Jul 22 2012 *)
%o (PARI) Vec(x*(1+x+x^2-2*x^3+4*x^4+x^6+x^7-x^8)/((1-x)^4*(1+x+x^2)^4) + O(x^100)) \\ _Colin Barker_, Dec 02 2015
%Y Cf. A000463, A010872.
%K nonn,easy
%O 1,4
%A _Mohammad K. Azarian_, Aug 30 2005
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