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 A067211 Number of n X n 0..3 matrices with all row and column sums equal. 1
 4, 16, 340, 89520, 290838284, 12092687195284, 6675338514190905402, 50327836869668591230004816, 5292118931181847999077738163123240, 7888144623867099277720906683959732404332016, 168815361056027801755263418243053345902341535059333028 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..11. EXAMPLE Some solutions for n=3 ..2..1..1....1..3..1....0..2..1....2..2..2....0..0..3....1..2..1....1..3..3 ..0..1..3....1..1..3....3..0..0....2..2..2....2..1..0....0..1..3....3..1..3 ..2..2..0....3..1..1....0..1..2....2..2..2....1..2..0....3..1..0....3..3..1 CROSSREFS Row 3 of A202784. Sequence in context: A023114 A207851 A202681 * A156337 A000874 A061580 Adjacent sequences: A067208 A067209 A067210 * A067212 A067213 A067214 KEYWORD nonn AUTHOR R. H. Hardin, Feb 20 2002 EXTENSIONS Added one term and example - R. H. Hardin, Jan 05, 2012 a(7)-a(10) from Andrew Howroyd, Jun 01 2017 a(11) from Sean A. Irvine, Dec 14 2023 STATUS approved

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Last modified June 14 01:54 EDT 2024. Contains 373391 sequences. (Running on oeis4.)