A267718 Number of nX7 0..1 arrays with every repeated value in every row and column greater than the previous repeated value.

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

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences: A267715 A267716 A267717 * A267719 A267720 A267721

Keyword

nonn

Author

R. H. Hardin, Jan 19 2016

Status

approved