Number of fixed polyominoes with 2n-1 cells and width and height both equal to n.

A334551

Number of fixed polyominoes with 2n-1 cells and width and height both equal to n.

Terms

    a(0) =1a(1) =4a(2) =25a(3) =120a(4) =497a(5) =1924a(6) =7265a(7) =27288a(8) =102745a(9) =388692a(10) =1477721a(11) =5643064a(12) =21632785a(13) =83204260a(14) =320932177a(15) =1240939448a(16) =4808642313a(17) =18668848852a(18) =72601081385a(19) =282762109272

External references