Number of Motzkin paths of length n with no level steps at even level.

Terms

a(0) =1a(1) =0a(2) =1a(3) =1a(4) =3a(5) =5a(6) =12a(7) =24a(8) =55a(9) =119a(10) =272a(11) =612a(12) =1411a(13) =3247a(14) =7565a(15) =17667a(16) =41561a(17) =98099a(18) =232696a(19) =553784a(20) =1322813a(21) =3169065a(22) =7614583a(23) =18342921a(24) =44294991a(25) =107200829a(26) =259983346a(27) =631718606a(28) =1537737567a(29) =3749440151