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A206260
Number of (n+1) X 2 0..1 arrays with the number of rightwards and downwards edge increases in each 2 X 2 subblock equal to the number in all its horizontal and vertical neighbors.
1
16, 24, 34, 50, 72, 105, 154, 229, 345, 527, 815, 1274, 2009, 3190, 5092, 8160, 13114, 21119, 34060, 54987, 88835, 143589, 232169, 375480, 607347, 982500, 1589494, 2571614, 4160700, 6731877, 10892110, 17623489, 28515069, 46137995, 74652467
OFFSET
1,1
COMMENTS
Column 1 of A206267.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) - 5*a(n-2) + a(n-3) + 2*a(n-4) - a(n-5) for n>6.
Empirical g.f.: x*(16 - 40*x + 18*x^2 + 18*x^3 - 14*x^4 + x^5) / ((1 - x)^3*(1 - x - x^2)). - Colin Barker, Jun 14 2018
EXAMPLE
Some solutions for n=4:
..0..0....0..1....0..1....1..1....1..0....1..1....0..0....1..1....0..0....1..0
..0..1....1..0....1..0....0..0....0..0....1..1....1..0....1..0....0..0....1..1
..1..0....0..1....0..1....0..0....0..0....1..1....1..1....0..0....0..0....0..1
..0..1....1..0....0..1....0..0....0..0....1..0....0..1....0..0....0..0....0..0
..1..0....0..1....1..0....0..0....0..0....1..0....0..0....0..0....0..0....1..0
CROSSREFS
Cf. A206267.
Sequence in context: A273801 A163284 A100316 * A036328 A067028 A110893
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 05 2012
STATUS
approved