A347679 Irregular triangle read by rows: T(n,k) (1 <= k <= 2*n) = number of n X k Baxter matrices in which all row sums are 2.
0, 1, 0, 0, 2, 4, 0, 0, 0, 3, 24, 26, 0, 0, 0, 0, 8, 98, 284, 214, 0, 0, 0, 0, 0, 19, 374, 1922, 3496, 2030, 0, 0, 0, 0, 0, 0, 44, 1342, 10620, 33398, 44674, 21174, 0, 0, 0, 0, 0, 0, 0, 111, 4596, 51904, 245684, 554500, 589092, 236410
Offset: 1
Examples
The T(4,5)=8 matrices of size 4 X 5 are . 0 0 0 1 1 0 0 0 1 1 0 1 0 0 1 1 0 0 0 1 0 0 1 1 0 1 0 0 1 0 0 0 1 1 0 0 0 1 1 0 0 1 1 0 0 0 1 1 0 0 0 1 0 0 1 0 1 1 0 0 1 1 0 0 0 1 0 0 1 0 1 1 0 0 0 1 0 0 0 1 . 1 0 0 0 1 1 0 0 1 0 1 1 0 0 0 1 1 0 0 0 0 1 1 0 0 0 1 1 0 0 0 1 0 0 1 0 1 1 0 0 0 0 1 1 0 1 0 0 1 0 0 0 1 1 0 0 0 1 1 0 1 0 0 0 1 0 0 0 1 1 0 1 0 0 1 0 0 0 1 1
Links
- Don Knuth, Baxter matrices, Preprint, Sep 05 2021.