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A303316
Number of 4Xn 0..1 arrays with every element equal to 0, 1, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
8, 6, 11, 36, 50, 128, 439, 1085, 2431, 6452, 17455, 43514, 108524, 281615, 726261, 1839731, 4685152, 12025643, 30754258, 78396104, 200278695, 512290781, 1308785863, 3342222476, 8540451095, 21826102586, 55761123412, 142456533311
OFFSET
1,1
COMMENTS
Row 4 of A303314.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +5*a(n-3) +9*a(n-4) -3*a(n-5) -7*a(n-6) -2*a(n-7) for n>11
EXAMPLE
Some solutions for n=5
..0..1..1..1..0. .0..1..0..1..0. .0..0..0..1..0. .0..1..0..1..0
..0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0
..0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..0..0
..0..1..1..1..0. .0..0..0..1..0. .0..0..0..1..0. .0..1..0..1..1
CROSSREFS
Cf. A303314.
Sequence in context: A053744 A265118 A034085 * A340518 A173435 A184728
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 21 2018
STATUS
approved