Number of equivalence classes of ballot paths of length n for the string uu.

Terms

a(0) =1a(1) =2a(2) =3a(3) =5a(4) =8a(5) =14a(6) =24a(7) =42a(8) =73a(9) =128a(10) =224a(11) =393a(12) =689a(13) =1209a(14) =2121a(15) =3722a(16) =6531a(17) =11461a(18) =20112a(19) =35294a(20) =61936a(21) =108690a(22) =190737a(23) =334720a(24) =587392a(25) =1030801a(26) =1808929a(27) =3174449a(28) =5570769a(29) =9776018