Number of nonequivalent 3 X n nonnegative integer matrices with all column sums 3 and row sums n up to permutation of rows.

A333902

Number of nonequivalent 3 X n nonnegative integer matrices with all column sums 3 and row sums n up to permutation of rows.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =10a(4) =70a(5) =566a(6) =4781a(7) =41357a(8) =364470a(9) =3257830a(10) =29450557a(11) =268701797a(12) =2470513849a(13) =22862694505a(14) =212758007450

External references