Number of polyominoes with n cells and exactly one line of reflection symmetry, where that one line is parallel to the grid and passes through the center of at least one square.

A349328

Number of polyominoes with n cells and exactly one line of reflection symmetry, where that one line is parallel to the grid and passes through the center of at least one square.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =1a(4) =2a(5) =4a(6) =9a(7) =16a(8) =38a(9) =62a(10) =147a(11) =241a(12) =564a(13) =926a(14) =2148a(15) =3561a(16) =8195a(17) =13700a(18) =31349a(19) =52858a(20) =120357a(21) =204444a(22) =463712a(23) =792986a(24) =1792582a(25) =3083469a(26) =6950579a(27) =12018394a(28) =27023509a(29) =46943409

External references