Number of 4Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing.

A223921

Number of 4Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing.

Terms

    a(0) =15a(1) =225a(2) =2111a(3) =14123a(4) =74040a(5) =323394a(6) =1226491a(7) =4157102a(8) =12856218a(9) =36834899a(10) =98904313a(11) =251078009a(12) =606789828a(13) =1403779390a(14) =3122765753a(15) =6704628063a(16) =13936852281a(17) =28123662137a(18) =55220811463a(19) =105715542647a(20) =197678421680

External references