%I #22 Sep 14 2024 06:54:00
%S 0,0,1,2,3,6,15,30,55,110,231,462,903,1806,3655,7310,14535,29070,
%T 58311,116622,232903,465806,932295,1864590,3727815,7455630,14913991,
%U 29827982,59650503,119301006,238612935,477225870,954429895,1908859790,3817763271,7635526542
%N A084175 interleaved with 2*A084175.
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1,2,2,-4).
%F From _R. J. Mathar_, May 19 2008: (Start)
%F O.g.f.: x^2/((2*x-1)(x-1)(1+x)(1+2*x^2)).
%F a(2n) = A084175(n). a(2n+1) = 2*A084175(n).
%F a(n) = 2*a(n-1) - a(n-2) + 2*a(n-3) + 2*a(n-4) - 4*a(n-5). (End)
%t LinearRecurrence[{2, -1, 2, 2, -4}, {0, 0, 1, 2, 3}, 40] (* _Amiram Eldar_, Sep 13 2024 *)
%Y Cf. A084175.
%K nonn,easy
%O 0,4
%A _Paul Curtz_, May 18 2008
%E More terms from _R. J. Mathar_, May 19 2008