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A241115
Number of nX3 0..3 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..3 introduced in row major order
1
5, 178, 9918, 587555, 35000157, 2085879115, 124315318217, 7409032909403, 441568937568818, 26316947602316573, 1568456640467509976, 93478023005207665450, 5571171404819117025366, 332034737407500793137773
OFFSET
1,1
COMMENTS
Column 3 of A241119
LINKS
FORMULA
Empirical: a(n) = 60*a(n-1) -7*a(n-2) -972*a(n-3) -2112*a(n-4) -2660*a(n-5) +12008*a(n-6) +48742*a(n-7) +35629*a(n-8) -20302*a(n-9) -27711*a(n-10) -65688*a(n-11) -146133*a(n-12) -130104*a(n-13) -24426*a(n-14) +56268*a(n-15) +56538*a(n-16) +13284*a(n-17) -5103*a(n-18) -5346*a(n-19) -1458*a(n-20) for n>21
EXAMPLE
Some solutions for n=3
..0..1..1....0..1..2....0..0..1....0..0..1....0..1..0....0..1..2....0..1..2
..2..2..2....0..0..2....2..2..2....1..2..2....2..3..2....2..1..0....0..1..0
..3..1..3....1..2..0....0..3..0....2..3..0....0..0..3....2..3..3....1..0..1
CROSSREFS
Sequence in context: A157204 A248383 A200796 * A208196 A194571 A210931
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 16 2014
STATUS
approved