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A188823
Number of n X 8 binary arrays without the pattern 0 1 diagonally or antidiagonally.
1
256, 3025, 11664, 28561, 53824, 87616, 129600, 179776, 238144, 304704, 379456, 462400, 553536, 652864, 760384, 876096, 1000000, 1132096, 1272384, 1420864, 1577536, 1742400, 1915456, 2096704, 2286144, 2483776, 2689600, 2903616, 3125824
OFFSET
1,1
COMMENTS
Column 8 of A188824.
LINKS
FORMULA
Empirical: a(n) = 4096*n^2 - 11264*n + 7744 for n>4.
Empirical g.f.: x*(256 + 2257*x + 3357*x^2 + 2388*x^3 + 108*x^4 + 163*x^5 - 337*x^6) / (1 - x)^3. - Colin Barker, Apr 30 2018
EXAMPLE
Some solutions for 3 X 8:
..1..1..1..0..1..0..1..0....1..1..0..1..1..1..1..1....0..1..1..1..1..1..1..1
..0..1..0..1..0..1..0..0....1..0..1..0..1..1..0..1....0..0..1..0..1..1..1..0
..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..1
CROSSREFS
Cf. A188824.
Sequence in context: A235502 A236202 A236199 * A205935 A205928 A235665
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 11 2011
STATUS
approved