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A235951
Number of (n+1) X (5+1) 0..2 arrays colored with the upper median value of each 2 X 2 subblock.
1
7353, 5034, 2478, 3496, 5358, 6728, 9260, 14016, 20570, 26912, 36512, 56064, 82568, 107648, 146048, 224256, 330272, 430592, 584192, 897024, 1321088, 1722368, 2336768, 3588096, 5284352, 6889472, 9347072, 14352384, 21137408, 27557888
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 4*a(n-4) for n>13.
Empirical g.f.: x*(7353 + 5034*x + 2478*x^2 + 3496*x^3 - 24054*x^4 - 13408*x^5 - 652*x^6 + 32*x^7 - 862*x^8 - 528*x^10 + 288*x^12) / ((1 - 2*x^2)*(1 + 2*x^2)). - Colin Barker, Oct 20 2018
EXAMPLE
Some solutions for n=5:
..1..2..0..0..0..2....2..1..0..1..2..2....2..0..0..0..2..1....2..0..0..0..1..2
..2..1..0..1..2..1....1..2..0..0..0..1....1..2..1..0..1..2....1..2..1..0..1..2
..0..0..0..2..1..0....0..1..2..1..0..1....0..1..2..0..0..0....0..1..2..0..0..0
..0..1..2..0..0..0....0..0..0..2..0..0....0..0..0..2..1..0....0..0..0..2..1..0
..0..2..1..0..1..2....2..1..0..1..2..1....2..1..0..1..2..0....1..1..0..1..2..1
..2..1..0..0..2..2....2..2..0..0..0..2....0..2..0..0..0..2....2..2..0..0..1..2
CROSSREFS
Column 5 of A235954.
Sequence in context: A202566 A204507 A295002 * A219084 A284925 A128478
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 17 2014
STATUS
approved