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A377063
Array read by antidiagonals: T(n,k) is the number of {-1,0,1} n X k matrices with all rows and columns summing to zero up to permutations of rows.
7
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 4, 2, 1, 1, 1, 1, 10, 6, 3, 1, 1, 1, 1, 26, 30, 12, 3, 1, 1, 1, 1, 71, 166, 117, 18, 4, 1, 1, 1, 1, 197, 981, 1421, 345, 30, 4, 1, 1, 1, 1, 554, 5937, 20326, 9691, 1042, 42, 5, 1, 1, 1, 1, 1570, 36646, 307063, 336596, 63076, 2746, 63, 5, 1, 1
OFFSET
0,13
COMMENTS
Columns are not permutable.
Equivalently, the number of n X k 0..2 arrays with row sums k and column sums n up to permutations of rows.
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..434 (first 29 antidiagonals)
EXAMPLE
Array begins:
===================================================
n\k | 0 1 2 3 4 5 6 7 ...
----+----------------------------------------------
0 | 1 1 1 1 1 1 1 1 ...
1 | 1 1 1 1 1 1 1 1 ...
2 | 1 1 2 4 10 26 71 197 ...
3 | 1 1 2 6 30 166 981 5937 ...
4 | 1 1 3 12 117 1421 20326 307063 ...
5 | 1 1 3 18 345 9691 336596 12650093 ...
6 | 1 1 4 30 1042 63076 5328136 506525279 ...
7 | 1 1 4 42 2746 369036 76292516 18490880339 ...
...
CROSSREFS
Main diagonal is A377064.
Rows n=0..4 are A000012, A000012, A257520, A377065, A377066.
Columns k=0..4 are A000012, A000012, A008619, A377067, A377068.
Cf. A334549.
Sequence in context: A060097 A098120 A098873 * A257462 A337131 A046876
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Oct 14 2024
STATUS
approved