a(n) = Motzkin(n) - 2^(n - 1 + 0^n) = A001006(n) - A011782(n).

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =5a(6) =19a(7) =63a(8) =195a(9) =579a(10) =1676a(11) =4774a(12) =13463a(13) =37739a(14) =105442a(15) =294188a(16) =820699a(17) =2291243a(18) =6405310a(19) =17937140a(20) =50327731a(21) =141498983a(22) =398666071a(23) =1125566111a(24) =3184339189a(25) =9026625285a(26) =25636264044a(27) =72940663938a(28) =207889060481a(29) =593474349373