Number of different fixed (possibly) disconnected tetrominoes bounded (not necessarily tightly) by an n X n square.

A162674

Number of different fixed (possibly) disconnected tetrominoes bounded (not necessarily tightly) by an n X n square.

Terms

    a(0) =0a(1) =1a(2) =97a(3) =956a(4) =4780a(5) =16745a(6) =46921a(7) =112672a(8) =241536a(9) =474585a(10) =870265a(11) =1508716a(12) =2496572a(13) =3972241a(14) =6111665a(15) =9134560a(16) =13311136a(17) =18969297a(18) =26502321a(19) =36377020a(20) =49142380a(21) =65438681a(22) =86007097a(23) =111699776a(24) =143490400a(25) =182485225a(26) =229934601

External references