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A026764 a(n) = T(n, floor(n/2)), T given by A026758.

%I A026764 #8 Nov 01 2019 03:55:02
%S A026764 1,1,2,4,7,16,27,66,109,279,453,1201,1922,5242,8284,23133,36155,
%T A026764 103015,159435,462269,709246,2088146,3178992,9487405,14343567,
%U A026764 43328580,65099245,198798447,297015765,915950385,1361584755,4236322720
%N A026764 a(n) = T(n, floor(n/2)), T given by A026758.
%H A026764 G. C. Greubel, <a href="/A026764/b026764.txt">Table of n, a(n) for n = 0..1000</a>
%p A026764 T:= proc(n,k) option remember;
%p A026764    if n<0 then 0;
%p A026764    elif k=0 or k = n then 1;
%p A026764    elif type(n,'odd') and k <= (n-1)/2 then
%p A026764         procname(n-1,k-1)+procname(n-2,k-1)+procname(n-1,k) ;
%p A026764    else
%p A026764        procname(n-1,k-1)+procname(n-1,k) ;
%p A026764    end if ;
%p A026764 end proc;
%p A026764 seq(T(n, floor(n/2)), n=0..30); # _G. C. Greubel_, Oct 31 2019
%t A026764 T[n_, k_]:= T[n, k]= If[n<0, 0, If[k==0 || k==n, 1, If[OddQ[n] && k<=(n - 1)/2, T[n-1, k-1] + T[n-2, k-1] + T[n-1, k], T[n-1, k-1] + T[n-1, k] ]] ]; Table[T[n, Floor[n/2]], {n,0,30}] (* _G. C. Greubel_, Oct 31 2019 *)
%o A026764 (Sage)
%o A026764 @CachedFunction
%o A026764 def T(n, k):
%o A026764     if (n<0): return 0
%o A026764     elif (k==0 or k==n): return 1
%o A026764     elif (mod(n,2)==1 and k<=(n-1)/2): return T(n-1,k-1) + T(n-2,k-1) + T(n-1,k)
%o A026764     else: return T(n-1,k-1) + T(n-1,k)
%o A026764 [T(n, floor(n/2)) for n in (0..30)] # _G. C. Greubel_, Oct 31 2019
%Y A026764 Cf. A026758, A026759, A026760, A026761, A026762, A026763, A026765, A026766, A026767, A026768.
%K A026764 nonn
%O A026764 0,3
%A A026764 _Clark Kimberling_