Number of simple imperfect squared squares of order n up to symmetry.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =0a(10) =0a(11) =0a(12) =1a(13) =0a(14) =3a(15) =5a(16) =15a(17) =19a(18) =57a(19) =72a(20) =274a(21) =491a(22) =1766a(23) =3679a(24) =11158a(25) =24086a(26) =64754a(27) =132598a(28) =326042a(29) =667403