Number of n X n 0..2 matrices with row and column i=1..n having sum <= i*2.

A213956

Number of n X n 0..2 matrices with row and column i=1..n having sum <= i*2.

Terms

    a(0) =3a(1) =42a(2) =3186a(3) =1299735a(4) =2860343784

External references