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A303311
Number of nX5 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, 7, 24, 50, 139, 349, 853, 2180, 5525, 13824, 34900, 88161, 221923, 559409, 1411020, 3556271, 8964218, 22600998, 56974213, 143622769, 362071261, 912756908, 2300972077, 5800604608, 14622927344, 36863258801, 92929626827, 234268970653
OFFSET
1,1
COMMENTS
Column 5 of A303314.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +9*a(n-3) +2*a(n-4) +4*a(n-5) -10*a(n-6) -6*a(n-7) +4*a(n-9) for n>12
EXAMPLE
Some solutions for n=5
..0..1..1..1..0. .0..1..0..1..0. .0..0..0..1..0. .0..0..0..1..0
..0..1..0..1..0. .0..0..1..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..0..0..1..0. .0..0..0..1..0
..0..1..1..1..0. .0..0..0..1..0. .0..1..0..1..0. .1..1..0..1..0
CROSSREFS
Cf. A303314.
Sequence in context: A126937 A282471 A309877 * A267093 A090099 A365486
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 21 2018
STATUS
approved