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%I #15 Jan 01 2024 11:48:43
%S 0,1,1,3,4,10,14,34,48,116,164,396,560,1352,1912,4616,6528,15760,
%T 22288,53808,76096,183712,259808,627232,887040,2141504,3028544,
%U 7311552,10340096,24963200,35303296,85229696,120532992,290992384,411525376,993510144,1405035520
%N a(n) = 4*a(n-2) - 2*a(n-4).
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0, 4, 0, -2).
%F a(n) = A007068(n-2), n>2.
%F G.f.: -x^2*(-1-x+x^2)/(1-4*x^2+2*x^4). [Oct 14 2009]
%t LinearRecurrence[{0,4,0,-2},{0,1,1,3},30] (* _Harvey P. Dale_, May 21 2014 *)
%Y Cf A002530, A048788.
%K nonn,easy,less
%O 1,4
%A _Roger L. Bagula_ and _Gary W. Adamson_, Sep 07 2006
%E Definition replaced by recurrence - The Assoc. Editors of the OEIS, Oct 14 2009
%E More terms from _Harvey P. Dale_, May 21 2014