A377068 Number of n X 4 0..2 matrices with row sums 4 and column sums n up to permutations of rows.

1, 1, 10, 30, 117, 345, 1042, 2746, 7063, 16759, 38440, 83476, 175473, 354105, 694278, 1318222, 2440888, 4402852, 7770908, 13418156, 22734824, 37807500, 61839510, 99526422, 157858478, 246864782, 381087734, 580990046, 875572808, 1304930876, 1924761300, 2810843268

Offset: 0

Author

Andrew Howroyd, Oct 15 2024

Keywords

• nonn

Comments

Also, the number of n X 4 {-1,0,1} matrices with all rows and columns summing to zero up to permutations of rows.

Examples

			The a(2) = 10 matrices are:
  [1 1 2 0]  [1 2 1 0]  [1 2 0 1]  [2 1 1 0]  [2 1 0 1]  [2 0 1 1]
  [1 1 0 2]  [1 0 1 2]  [1 0 2 1]  [0 1 1 2]  [0 1 2 1]  [0 2 1 1]
.
  [1 1 1 1]  [2 2 0 0]  [2 0 2 0]  [2 0 0 2]
  [1 1 1 1]  [0 0 2 2]  [0 2 0 2]  [0 2 2 0]
		

Crossrefs

Column k=4 of A377063.

Cf. A172642, A377066, A377067.