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A231445
Number of (n+1) X (2+1) 0..3 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with values 0..3 introduced in row major order.
1
3, 15, 97, 715, 5643, 46075, 382341, 3196783, 26821757, 225400759, 1895576427, 15946759047, 134174450017, 1129009038167, 9500331770337, 79944094951011, 672723905279179, 5660941011339603, 47636625510849789, 400860827109560351
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 19*a(n-1) - 133*a(n-2) + 461*a(n-3) - 867*a(n-4) + 881*a(n-5) - 468*a(n-6) + 108*a(n-7).
Empirical g.f.: x*(3 - 42*x + 211*x^2 - 516*x^3 + 645*x^4 - 402*x^5 + 108*x^6) / ((1 - x)*(1 - 5*x + 5*x^2 - 2*x^3)*(1 - 13*x + 45*x^2 - 54*x^3)). - Colin Barker, Sep 29 2018
EXAMPLE
Some solutions for n=7:
..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..1..1....0..0..1....0..1..1....0..0..1....0..0..1....0..0..1....0..0..1
..1..1..1....0..1..0....1..1..2....0..1..1....1..1..0....0..1..0....0..1..2
..0..0..2....1..0..2....1..2..2....0..0..0....0..0..0....1..0..0....1..2..2
..0..2..0....0..2..2....3..3..0....1..1..1....0..0..0....0..0..1....2..3..3
..2..0..2....2..0..0....3..0..0....1..2..2....0..2..2....0..1..1....3..3..2
..0..2..1....0..0..3....2..2..3....2..2..0....2..2..3....1..1..1....2..2..3
..2..1..1....3..3..3....2..3..3....2..0..0....2..3..3....2..2..2....2..3..3
CROSSREFS
Column 2 of A231451.
Sequence in context: A370210 A079689 A262751 * A108442 A060148 A143435
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 09 2013
STATUS
approved