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

Terms

a(0) =0a(1) =0a(2) =1a(3) =2a(4) =4a(5) =8a(6) =17a(7) =36a(8) =83a(9) =202a(10) =519a(11) =1382a(12) =3766a(13) =10352a(14) =28551a(15) =78756a(16) =217224a(17) =599542a(18) =1657983a(19) =4598766a(20) =12803044a(21) =35785664a(22) =100412731a(23) =282753476a(24) =798690091a(25) =2262087814a(26) =6421507153a(27) =18265543282a(28) =52047980674a(29) =148554917816