The number of non-palindromic Motzkin paths of length n.

Terms

a(0) =0a(1) =0a(2) =0a(3) =2a(4) =4a(5) =16a(6) =38a(7) =114a(8) =288a(9) =800a(10) =2092a(11) =5702a(12) =15244a(13) =41568a(14) =112884a(15) =309822a(16) =851344a(17) =2354656a(18) =6530336a(19) =18193238a(20) =50834716a(21) =142530256a(22) =400713502a(23) =1129710694a(24) =3192584432a(25) =9043259136a(26) =25669403892a(27) =73007358218a(28) =208022076292a(29) =593741582912