Number of free tree-like convex polyominoes with n cells.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =10a(5) =21a(6) =49a(7) =104a(8) =227a(9) =468a(10) =976a(11) =1978a(12) =4030a(13) =8095a(14) =16313a(15) =32656a(16) =65503a(17) =130986a(18) =262252a(19) =524330a(20) =1049054a(21) =2097549a(22) =4195633a(23) =8389840