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A231420
Number of (1+1) X (n+1) 0..2 arrays with no element equal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order.
1
9, 71, 514, 3838, 28486, 212060, 1578180, 11748804, 87465304, 651171800, 4847955288, 36093104816, 268714229264, 2000587354768, 14894452176096, 110889806477664, 825579209354848, 6146471657514944, 45760738536130624
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) + 4*a(n-2) - 58*a(n-3) - 24*a(n-4) + 40*a(n-5) - 16*a(n-6).
Empirical g.f.: x*(9 - x - 90*x^2 - 36*x^3 + 60*x^4 - 24*x^5) / (1 - 8*x - 4*x^2 + 58*x^3 + 24*x^4 - 40*x^5 + 16*x^6). - Colin Barker, Sep 28 2018
EXAMPLE
Some solutions for n=6:
..0..0..1..2..0..0..2....0..0..1..1..0..2..0....0..1..2..2..1..0..2
..1..2..0..2..2..0..1....1..1..2..2..1..1..1....0..1..0..1..1..2..2
CROSSREFS
Row 1 of A231419.
Sequence in context: A227848 A226846 A226711 * A081900 A164551 A178869
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 08 2013
STATUS
approved