Number of Motzkin excursions of length n with an even number of humps and an odd number of peaks.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =2a(6) =8a(7) =26a(8) =76a(9) =212a(10) =568a(11) =1504a(12) =3968a(13) =10526a(14) =28192a(15) =76398a(16) =209268a(17) =578396a(18) =1609376a(19) =4499336a(20) =12620080a(21) =35482718a(22) =99958776a(23) =282107702a(24) =797637908a(25) =2259545652a(26) =6413273704a(27) =18238099464a(28) =51963195440a(29) =148315593178