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

Terms

a(0) =0a(1) =0a(2) =1a(3) =4a(4) =13a(5) =40a(6) =119a(7) =348a(8) =1011a(9) =2928a(10) =8471a(11) =24516a(12) =71023a(13) =206024a(14) =598513a(15) =1741332a(16) =5073733a(17) =14804160a(18) =43252855a(19) =126526756a(20) =370551287a(21) =1086365336a(22) =3188090101a(23) =9364411252a(24) =27529374201a(25) =80993754352a(26) =238463467529a(27) =702563144252