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URL: https://oeis.org/A229870

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A229870
T(n,k)=Number of n X n 0..k arrays with corresponding row and column sums equal.
9
2, 3, 8, 4, 27, 80, 5, 64, 1215, 2432, 6, 125, 8704, 384183, 247552, 7, 216, 40625, 15106048, 923742873, 88060928, 8, 343, 143856, 266515625, 354003288064, 17451302074317, 112371410944, 9, 512, 420175, 2805425280, 36821326171875
OFFSET
1,1
COMMENTS
Table starts
......2.........3............4..............5................6...........7
......8........27...........64............125..............216.........343
.....80......1215.........8704..........40625...........143856......420175
...2432....384183.....15106048......266515625.......2805425280.20610104767
.247552.923742873.354003288064.36821326171875.1656812779036416
LINKS
FORMULA
Empirical for row n:
n=1: a(n) = n + 1
n=2: a(n) = n^3 + 3*n^2 + 3*n + 1
n=3: [polynomial of degree 7]
n=4: [polynomial of degree 13]
EXAMPLE
Some solutions for n=4 k=4
..0..0..0..1....0..0..0..1....0..0..0..0....0..0..1..1....0..0..1..1
..0..1..2..1....0..0..3..4....0..0..3..3....0..1..0..3....0..0..2..2
..1..0..0..3....1..4..2..0....0..4..0..2....1..3..4..0....1..3..4..1
..0..3..2..1....0..3..2..2....0..2..3..2....1..0..3..2....1..1..2..0
CROSSREFS
Row 2 is A000578(n+1)
Row 3 is A168364(n+1)
Sequence in context: A093898 A194931 A195248 * A202651 A334859 A084110
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Oct 01 2013
STATUS
approved