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A267718
Number of nX7 0..1 arrays with every repeated value in every row and column greater than the previous repeated value.
1
20, 400, 1866, 7879, 20226, 54887, 116036, 255009, 481390, 932245, 1627470, 2893983, 4765598, 7967260, 12535320, 20000374, 30337594, 46665892, 68699820, 102616722, 147369478, 214889742, 302259706, 431988823, 597033836, 838908027
OFFSET
1,1
COMMENTS
Column 7 of A267719.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +12*a(n-2) -26*a(n-3) -65*a(n-4) +156*a(n-5) +208*a(n-6) -572*a(n-7) -429*a(n-8) +1430*a(n-9) +572*a(n-10) -2574*a(n-11) -429*a(n-12) +3432*a(n-13) -3432*a(n-15) +429*a(n-16) +2574*a(n-17) -572*a(n-18) -1430*a(n-19) +429*a(n-20) +572*a(n-21) -208*a(n-22) -156*a(n-23) +65*a(n-24) +26*a(n-25) -12*a(n-26) -2*a(n-27) +a(n-28) for n>30
EXAMPLE
Some solutions for n=5
..0..0..1..0..1..0..1....0..1..0..1..0..1..1....1..0..1..0..1..0..0
..1..1..0..1..0..1..0....1..1..0..1..0..1..0....0..1..0..1..0..1..0
..1..0..1..0..1..0..1....0..0..1..0..1..0..1....1..0..1..0..1..0..1
..0..0..1..1..0..1..0....0..1..0..1..0..1..0....0..1..0..0..1..1..0
..1..1..0..1..0..1..0....1..0..1..0..1..0..0....0..1..0..1..0..1..1
CROSSREFS
Cf. A267719.
Sequence in context: A209080 A090051 A089957 * A207402 A207751 A207127
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 19 2016
STATUS
approved