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A228752
Number of n X 6 binary arrays with top left element equal to 1 and no two ones adjacent horizontally or antidiagonally.
1
8, 119, 1712, 24246, 342207, 4823826, 67970044, 957616341, 13491214832, 190066959598, 2677695197199, 37723794440794, 531458704862804, 7487272853619205, 105481862639606840, 1486044856081515654
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 21*a(n-1) - 112*a(n-2) + 217*a(n-3) - 157*a(n-4) + 36*a(n-5) for n>6.
Empirical g.f.: x*(8 - 49*x + 109*x^2 - 114*x^3 + 218*x^4 - 78*x^5) / (1 - 21*x + 112*x^2 - 217*x^3 + 157*x^4 - 36*x^5). - Colin Barker, Sep 12 2018
EXAMPLE
Some solutions for n=4:
..1..0..1..0..0..0....1..0..1..0..0..0....1..0..0..1..0..1....1..0..0..0..0..1
..1..0..1..0..0..1....0..0..0..0..1..0....1..0..0..0..0..1....1..0..0..0..0..1
..0..0..1..0..0..1....0..0..1..0..1..0....0..0..0..0..0..1....1..0..0..0..0..0
..0..0..0..1..0..0....1..0..1..0..0..1....0..1..0..1..0..1....0..1..0..0..1..0
CROSSREFS
Column 6 of A228754.
Sequence in context: A267752 A318009 A368911 * A360978 A116008 A086302
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 02 2013
STATUS
approved