Number of fixed tree-like convex polyominoes.

Terms

a(0) =1a(1) =2a(2) =6a(3) =18a(4) =51a(5) =134a(6) =328a(7) =758a(8) =1677a(9) =3594a(10) =7530a(11) =15530a(12) =31687a(13) =64190a(14) =129420a(15) =260142a(16) =521889a(17) =1045730a(18) =2093806a(19) =4190402a(20) =8384091a(21) =16772022a(22) =33548496a(23) =67102118a(24) =134210101a(25) =268426874a(26) =536861298a(27) =1073731098a(28) =2147471727a(29) =4294954094