Number of n X 3 0..3 arrays with rows nondecreasing and antidiagonals unimodal.

A224019

Number of n X 3 0..3 arrays with rows nondecreasing and antidiagonals unimodal.

Terms

    a(0) =20a(1) =400a(2) =6796a(3) =112436a(4) =1859020a(5) =30756756a(6) =508916456a(7) =8420768936a(8) =139333478144

External references