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A231799
Number of (n+1) X (1+1) 0..1 arrays with no element having a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors equal to one.
1
5, 13, 32, 79, 200, 500, 1249, 3133, 7845, 19640, 49195, 123202, 308530, 772687, 1935097, 4846171, 12136616, 30394575, 76119168, 190630456, 477408937, 1195607773, 2994242313, 7498685908, 18779471815, 47030715498, 117782237374
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = a(n-1) + 2*a(n-2) + 5*a(n-3) - 2*a(n-5) - 4*a(n-6).
Empirical g.f.: x*(5 + 8*x + 9*x^2 - 4*x^3 - 8*x^4 - 8*x^5) / (1 - x - 2*x^2 - 5*x^3 + 2*x^5 + 4*x^6). - Colin Barker, Oct 01 2018
EXAMPLE
Some solutions for n=7:
..0..1....0..0....1..1....0..0....1..1....1..0....0..1....0..0....0..0....0..0
..0..0....0..1....0..0....0..0....0..0....0..0....0..0....1..0....0..0....0..0
..0..0....0..1....0..0....0..0....0..0....0..0....1..0....0..1....0..1....0..0
..0..0....0..0....1..0....0..0....0..1....0..1....0..0....0..0....0..0....1..0
..0..0....0..1....0..0....1..0....0..1....0..1....1..0....0..0....0..1....0..0
..0..1....0..0....1..0....0..0....0..0....0..0....1..0....1..1....0..1....0..0
..0..0....0..0....0..0....0..1....0..0....1..0....0..0....0..0....0..0....0..0
..1..0....0..0....1..0....0..0....1..1....0..0....1..0....0..0....0..1....0..0
CROSSREFS
Column 1 of A231806.
Sequence in context: A271902 A272539 A066184 * A146924 A342032 A272161
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 13 2013
STATUS
approved