Number of balanced ordered trees with n nodes.

Terms

a(0) =0a(1) =1a(2) =1a(3) =2a(4) =3a(5) =5a(6) =8a(7) =14a(8) =24a(9) =43a(10) =77a(11) =140a(12) =256a(13) =472a(14) =874a(15) =1628a(16) =3045a(17) =5719a(18) =10780a(19) =20388a(20) =38674a(21) =73562a(22) =140268a(23) =268066a(24) =513350a(25) =984911a(26) =1892875a(27) =3643570a(28) =7023562a(29) =13557020