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A303317
Number of 5Xn 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
16, 9, 19, 74, 139, 410, 1799, 5907, 16494, 53290, 184915, 593160, 1846238, 5986532, 19644799, 63120477, 201894029, 652765881, 2113653016, 6806905917, 21913260238, 70736938785, 228339832475, 736091706666, 2373144545904, 7656031069031
OFFSET
1,1
COMMENTS
Row 5 of A303314.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) -a(n-2) +11*a(n-3) +21*a(n-4) -13*a(n-5) +5*a(n-6) -37*a(n-7) -34*a(n-8) +4*a(n-9) -20*a(n-10) +18*a(n-11) -7*a(n-12) for n>16
EXAMPLE
Some solutions for n=5
..0..1..0..1..0. .0..0..0..1..0. .0..1..0..1..0. .0..0..0..1..0
..0..0..0..1..0. .0..1..0..1..0. .0..1..1..1..0. .0..1..0..1..0
..0..1..1..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0
..0..1..0..0..0. .0..0..0..1..0. .0..1..0..0..0. .0..1..0..0..0
..0..1..0..1..1. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0
CROSSREFS
Cf. A303314.
Sequence in context: A070688 A281719 A103167 * A154615 A040242 A306378
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 21 2018
STATUS
approved