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A203564
T(n,k) = Number of n X k 0..2 arrays with row sums equal and column sums equal.
7
3, 3, 3, 3, 9, 3, 3, 9, 9, 3, 3, 33, 87, 33, 3, 3, 53, 177, 177, 53, 3, 3, 183, 993, 5673, 993, 183, 3, 3, 395, 10833, 32613, 32613, 10833, 395, 3, 3, 1249, 35619, 513903, 2577513, 513903, 35619, 1249, 3, 3, 3141, 219873, 7343451, 39612503, 39612503, 7343451
OFFSET
1,1
COMMENTS
Table starts:
.3....3.......3..........3...........3............3............3..............3
.3....9.......9.........33..........53..........183..........395...........1249
.3....9......87........177.........993........10833........35619.........219873
.3...33.....177.......5673.......32613.......513903......7343451......185804265
.3...53.....993......32613.....2577513.....39612503...1509893003....59794281893
.3..183...10833.....513903....39612503...8459809773.360255871643.37057831534783
.3..395...35619....7343451..1509893003.360255871643
.3.1249..219873..185804265.59794281893
.3.3141.2083713.1849858773
.3.9459.8710539
LINKS
EXAMPLE
Some solutions for n=5 and k=3:
..2..2..2....1..2..0....2..1..0....2..1..0....1..2..0....2..1..0....1..2..0
..2..2..2....2..0..1....1..1..1....1..1..1....2..0..1....2..1..0....0..1..2
..2..2..2....0..1..2....2..0..1....1..1..1....0..1..2....0..2..1....1..2..0
..2..2..2....2..0..1....0..2..1....0..2..1....2..0..1....0..1..2....2..0..1
..2..2..2....0..2..1....0..1..2....1..0..2....0..2..1....1..0..2....1..0..2
CROSSREFS
Diagonal is A202779.
Sequence in context: A007428 A184099 A074816 * A369716 A365345 A375230
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jan 03 2012
STATUS
approved