Floor-Sqrt transform of the numbers binomial(3*n,n)/(2*n+1) (A001764).

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =7a(5) =16a(6) =37a(7) =88a(8) =207a(9) =496a(10) =1196a(11) =2900a(12) =7075a(13) =17344a(14) =42693a(15) =105473a(16) =261397a(17) =649638a(18) =1618527a(19) =4041401a(20) =10111385a(21) =25343883a(22) =63627940a(23) =159982510a(24) =402802976a(25) =1015454569a(26) =2562911901a(27) =6475519561a(28) =16377581829a(29) =41459980288