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A241330
Number of 3Xn 0..3 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..3 introduced in row major order
1
5, 85, 2344, 68935, 2034543, 60066019, 1773370241, 52356524981, 1545760698649, 45636645554004, 1347364712395962, 39779252976746762, 1174432544392935470, 34673647645893709738, 1023695951556996550068, 30223338828856554979455
OFFSET
1,1
COMMENTS
Row 3 of A241328
LINKS
FORMULA
Empirical: a(n) = 31*a(n-1) -26*a(n-2) -530*a(n-3) +271*a(n-4) +1431*a(n-5) +437*a(n-6) +157*a(n-7) -438*a(n-8) -846*a(n-9) -243*a(n-10) -243*a(n-11) for n>13
EXAMPLE
Some solutions for n=4
..0..1..0..2....0..1..2..1....0..1..2..1....0..1..0..1....0..1..2..3
..0..1..1..2....3..1..3..2....3..0..3..0....2..3..1..1....1..1..3..2
..1..3..1..0....1..0..3..1....0..2..1..3....1..3..1..0....1..0..1..3
CROSSREFS
Sequence in context: A188918 A349936 A218139 * A301435 A280575 A318635
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 19 2014
STATUS
approved