Catalan transform of the 3-Fibonacci sequence A006190.

Terms

a(0) =0a(1) =1a(2) =4a(3) =18a(4) =83a(5) =387a(6) =1815a(7) =8541a(8) =40276a(9) =190182a(10) =898844a(11) =4250780a(12) =20111394a(13) =95181166a(14) =450565602a(15) =2133227418a(16) =10101126723a(17) =47834649675a(18) =226540406571