Number of chiral pairs of polyominoes with n cells.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =2a(5) =6a(6) =25a(7) =88a(8) =335a(9) =1215a(10) =4534a(11) =16823a(12) =63159a(13) =237679a(14) =900341a(15) =3423201a(16) =13073163a(17) =50095285a(18) =192599091a(19) =742576616a(20) =2870584814a(21) =11122879867a(22) =43191525139a(23) =168046317330a(24) =654998425237