a(n) is the number of 3 X 3 matrices with elements 1..n where at least one row and at least one column is strictly increasing.

A390925

a(n) is the number of 3 X 3 matrices with elements 1..n where at least one row and at least one column is strictly increasing.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =243a(4) =8608a(5) =100324a(6) =671092a(7) =3185367a(8) =11947344a(9) =37713112a(10) =104318488a(11) =259918219a(12) =594918544a(13) =1269236540a(14) =2552136236a(15) =4878573167a(16) =8926725856a(17) =15722204656a(18) =26775305456a(19) =44258617955a(20) =71233305536a(21) =111933446228a(22) =172118961828a(23) =259508864967a(24) =384307821744a(25) =559840360520

External references