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A253030
Number of (n+2) X (2+2) 0..2 arrays with every consecutive three elements in every row and column having exactly two distinct values, and new values 0 upwards introduced in row major order.
1
1647, 12987, 102060, 802899, 6320511, 49756086, 391717269, 3084008175, 24280718976, 191165802975, 1505081513979, 11849778354006, 93295489901625, 734532751313235, 5783113524612744, 45531534681929547, 358478297068844223
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) - 5*a(n-2) - 10*a(n-3) - 174*a(n-4) + 80*a(n-5) + 160*a(n-6).
Empirical g.f.: 27*x*(61 - 68*x - 244*x^2 - 1268*x^3 + 784*x^4 + 1280*x^5) / (1 - 9*x + 5*x^2 + 10*x^3 + 174*x^4 - 80*x^5 - 160*x^6). - Colin Barker, Dec 08 2018
EXAMPLE
Some solutions for n=3:
..0..1..1..2....0..1..0..0....0..1..0..1....0..1..1..0....0..1..1..2
..2..2..0..0....0..0..2..2....2..0..2..2....0..2..2..1....0..0..2..2
..2..1..1..2....2..1..2..2....2..1..2..1....1..2..2..0....2..1..2..1
..0..2..0..0....0..0..1..0....1..0..0..1....1..0..1..0....0..1..1..2
..0..1..0..0....0..1..1..0....2..0..2..0....0..2..2..1....0..0..1..1
CROSSREFS
Column 2 of A253035.
Sequence in context: A247077 A093059 A255620 * A252684 A203864 A154075
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 26 2014
STATUS
approved