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%I #16 Oct 03 2017 02:13:23
%S 0,0,0,0,0,0,0,0,4,4,18,48,100,294,648,1584,3840,8820,21168,49284,
%T 115248,270400,628660,1468548,3420150,7960000,18539400,43120350,
%U 100328400,233365440,542672640,1262045880,2934442944,6822962664,15863704528,36881698048,85746672900,199347278724,463445232298
%N a(n) = P(n)^3 - P(n)^2 where P(n) = A000931(n).
%H G. C. Greubel, <a href="/A133039/b133039.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (2,2,1,-9,3,-9,3,-3,15,-9,9,-3,1,-2,1,-1).
%F a(n) = P(n)^3 - P(n)^2 = A000931(n)^3 - A000931(n)^2.
%F G.f.: 2*x^8*(x^7-x^6+2*x^5+x^2-2*x+2) / ((x-1) * (x^3-2*x^2+3*x-1) * (x^3-x^2+2*x-1) * (x^3-x-1) * (x^6+3*x^5+5*x^4+5*x^3+5*x^2+3*x+1)). - _Colin Barker_, Sep 18 2013
%e a(10)=18 because Padovan(10)=3 and 3^3=27 and 3^2=9 and 27-9=18.
%t P[0] := 1; P[1] := 0; P[2] := 0; P[n_] := P[n] = P[n - 2] + P[n - 3]; Table[P[n]^3 - P[n]^2, {n, 0, 50}] (* _G. C. Greubel_, Oct 02 2017 *)
%o (PARI) x='x+O('x^50); concat([0, 0, 0, 0, 0, 0, 0, 0], Vec(2*x^8*(x^7-x^6+2*x^5+x^2-2*x+2)/((x -1)*(x^3-2*x^2+3*x-1)*(x^3-x^2+2*x-1)*(x^3-x-1)*(x^6+3*x^5+5*x^4 +5*x^3 +5*x^2+3*x+1)))) \\ _G. C. Greubel_, Oct 02 2017
%Y Cf. A000290, A000578, A045991. Padovan sequence: A000931.
%K easy,nonn
%O 0,9
%A _Omar E. Pol_, Nov 02 2007
%E Incorrect initial zero of the sequence deleted by _Colin Barker_, Sep 18 2013
%E Added more terms, _Joerg Arndt_, Sep 18 2013