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A205251
Number of (n+1) X 5 0..1 arrays with the number of clockwise edge increases in every 2 X 2 subblock the same.
1
328, 3416, 36304, 387328, 4136296, 44183032, 471988176, 5042151648, 53864590280, 575428804376, 6147238485232, 65670238411328, 701547599923496, 7494552376793144, 80063441950649104, 855308552375931040
OFFSET
1,1
COMMENTS
Column 4 of A205255.
LINKS
FORMULA
Empirical: a(n) = 17*a(n-1) - 81*a(n-2) + 157*a(n-3) - 140*a(n-4) + 56*a(n-5) - 8*a(n-6).
Empirical g.f.: 8*x*(41 - 270*x + 600*x^2 - 580*x^3 + 244*x^4 - 36*x^5) / ((1 - x)*(1 - 16*x + 65*x^2 - 92*x^3 + 48*x^4 - 8*x^5)). - Colin Barker, Jun 11 2018
EXAMPLE
Some solutions for n=4:
..1..0..0..0..0....0..0..1..0..0....0..0..0..1..0....0..0..0..1..0
..1..1..0..1..0....0..1..1..1..0....1..1..0..1..0....0..1..0..0..0
..1..0..0..1..1....0..0..0..1..0....0..0..0..0..0....1..1..0..1..0
..1..1..1..1..0....1..0..1..1..0....1..1..0..1..0....0..0..0..0..0
..0..0..1..0..0....1..1..1..0..0....1..0..0..1..0....1..1..1..0..1
CROSSREFS
Cf. A205255.
Sequence in context: A239536 A237505 A183848 * A138078 A232140 A231130
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 24 2012
STATUS
approved