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A228505 Number of nX7 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically, diagonally or antidiagonally. 1
13, 43, 684, 4749, 49101, 413786, 3862849, 34229311, 311423874, 2795565191, 25267110999, 227577191098, 2053397764249, 18510745379063, 166945846438154, 1505305762277273, 13574575402532525, 122405516285033798 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 7 of A228506
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) +50*a(n-2) -171*a(n-3) -514*a(n-4) +1800*a(n-5) +845*a(n-6) -5430*a(n-7) +704*a(n-8) +6175*a(n-9) -1762*a(n-10) -2810*a(n-11) +870*a(n-12) +392*a(n-13) -120*a(n-14)
EXAMPLE
Some solutions for n=4
..1..0..0..1..0..0..0....1..0..0..0..0..0..1....1..0..1..0..1..0..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..1
..0..1..0..0..0..0..0....1..0..0..0..0..0..1....1..0..1..0..0..0..0
..0..0..0..0..0..1..0....0..0..1..0..1..0..0....0..0..0..0..0..1..0
CROSSREFS
Sequence in context: A220612 A144236 A082689 * A224102 A123294 A015247
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 23 2013
STATUS
approved

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Last modified May 27 02:41 EDT 2024. Contains 372847 sequences. (Running on oeis4.)