Number of Motzkin meanders of length n with an odd number of humps.

Terms

a(0) =0a(1) =0a(2) =1a(3) =5a(4) =18a(5) =56a(6) =161a(7) =443a(8) =1196a(9) =3228a(10) =8823a(11) =24579a(12) =69810a(13) =201380a(14) =586843a(15) =1719081a(16) =5044584a(17) =14800352a(18) =43384747a(19) =127076015a(20) =372100654a(21) =1089864344a(22) =3194496987a(23) =9372984609a(24) =27532712140a(25) =80966582548a(26) =238342592353a(27) =702222958797