Number of Dyck paths of length 2n with nondecreasing peaks.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =9a(5) =21a(6) =51a(7) =126a(8) =316a(9) =800a(10) =2040a(11) =5230a(12) =13464a(13) =34773a(14) =90035a(15) =233590a(16) =607011a(17) =1579438a(18) =4114014a(19) =10725109a(20) =27979704a(21) =73035818a(22) =190737623a(23) =498320800a(24) =1302341411a(25) =3404552915a(26) =8902154847a(27) =23281653957a(28) =60897957049a(29) =159312797657