a(n) = T(n, floor(n/2)), T given by A026670.

Terms

a(0) =1a(1) =1a(2) =3a(3) =4a(4) =11a(5) =16a(6) =43a(7) =65a(8) =173a(9) =267a(10) =707a(11) =1105a(12) =2917a(13) =4597a(14) =12111a(15) =19196a(16) =50503a(17) =80380a(18) =211263a(19) =337284a(20) =885831a(21) =1417582a(22) =3720995a(23) =5965622a(24) =15652239a(25) =25130844a(26) =65913927a(27) =105954110a(28) =277822147a(29) =447015744