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%I #15 Jan 29 2016 10:22:32
%S 1,5,17,34,75,114,202,272,425,535,771,930,1267,1484,1940,2224,2817,
%T 3177,3925,4370,5291,5830,6942,7584,8905,9659,11207,12082,13875,14880,
%U 16936,18080,20417,21709,24345,25794,28747,30362,33650,35440,39081,41055,45067
%N a(n) = T(n,n-3), where T is the array in A026386.
%H Colin Barker, <a href="/A026394/b026394.txt">Table of n, a(n) for n = 3..1000</a>
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (1,3,-3,-3,3,1,-1)
%F G.f.: x^3*(1+4*x+9*x^2+5*x^3+8*x^4) / ((1-x)^4*(1+x)^3). - _Emeric Deutsch_, Feb 18 2004
%F From _Colin Barker_, Jan 29 2016: (Start)
%F a(n) = (18*n^3-9*(-1)^n*n^2-111*n^2+53*(-1)^n*n+243*n-75*(-1)^n-181)/32.
%F a(n) = (9*n^3-60*n^2+148*n-128)/16 for n even.
%F a(n) = (9*n^3-51*n^2+95*n-53)/16 for n odd.
%F (End)
%t t[n_, 0] := 1; t[n_, n_] := 1; t[n_, k_] := t[n, k] = Which[EvenQ@ n, t[n - 1, k - 1] + t[n - 1, k], OddQ@ n, t[n - 1, k - 1] + t[n - 1, k] + t[n - 2, k - 1]]; Table[t[n, n - 3], {n, 3, 45}] (* _Michael De Vlieger_, Jan 29 2016, after _Clark Kimberling_ at A026386 *)
%o (PARI) Vec(x^3*(1+4*x+9*x^2+5*x^3+8*x^4)/((1-x)^4*(1+x)^3) + O(x^100)) \\ _Colin Barker_, Jan 29 2016
%K nonn,easy
%O 3,2
%A _Clark Kimberling_