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A303718
Number of n X 7 0..1 arrays with every element unequal to 0, 1 or 5 king-move adjacent elements, with upper left element zero.
1
21, 23, 40, 161, 361, 741, 1592, 3469, 7416, 15880, 34193, 73457, 157645, 338676, 727589, 1562584, 3356196, 7209121, 15484337, 33258365, 71436088, 153437805, 329568008, 707878984, 1520453793, 3265780153, 7014565013, 15066579716
OFFSET
1,1
COMMENTS
Column 7 of A303719.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +3*a(n-3) +a(n-4) -a(n-5) -a(n-6) for n>9
EXAMPLE
Some solutions for n=5
..0..0..1..0..0..0..0. .0..0..1..0..0..0..0. .0..1..0..0..0..0..0
..0..0..0..0..0..0..0. .0..0..0..0..0..0..1. .0..0..0..0..0..0..1
..0..0..0..0..0..0..0. .0..0..0..0..0..0..0. .0..0..0..0..0..0..0
..0..0..0..0..0..0..0. .1..0..0..0..0..0..0. .0..0..0..0..0..0..0
..0..0..0..0..1..0..0. .0..0..0..0..0..0..0. .0..0..1..0..0..0..0
CROSSREFS
Cf. A303719.
Sequence in context: A229221 A157676 A227948 * A270108 A335189 A304269
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 29 2018
STATUS
approved