

A206198


Number of (n+1) X (n+1) 0..3 arrays with every 2 X 3 or 3 X 2 subblock having exactly one clockwise edge increases.


0



256, 1060, 5136, 32920, 118936, 484704, 3270240, 11893600, 48470400, 327024000, 1189360000, 4847040000, 32702400000, 118936000000, 484704000000, 3270240000000, 11893600000000, 48470400000000, 327024000000000
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS



LINKS



FORMULA

G.f.: 4*x*(64 + 265*x + 1284*x^2 + 1830*x^3 + 3234*x^4  7224*x^5  5440*x^6) / (1  100*x^3).
a(n) = 100*a(n3) for n>7.
(End)


EXAMPLE

Some solutions for n=4
..3..3..2..0..0....2..3..3..2..2....2..2..2..1..0....0..1..1..2..2
..3..3..3..0..0....2..3..3..3..1....3..2..2..2..0....0..1..1..1..2
..0..3..3..3..0....2..2..3..3..3....1..1..2..2..2....0..0..1..1..1
..0..0..3..3..3....2..2..2..3..3....1..1..1..2..2....0..0..0..1..1
..0..0..0..3..3....1..2..2..2..2....2..1..1..1..1....1..0..0..0..0


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



