Super ballot numbers: 60*(2n)!/(n!*(n+3)!).

Terms

a(0) =10a(1) =5a(2) =6a(3) =10a(4) =20a(5) =45a(6) =110a(7) =286a(8) =780a(9) =2210a(10) =6460a(11) =19380a(12) =59432a(13) =185725a(14) =589950a(15) =1900950a(16) =6203100a(17) =20470230a(18) =68234100a(19) =229514700a(20) =778354200a(21) =2659376850a(22) =9148256364a(23) =31667041260a(24) =110248217720a(25) =385868762020