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A302620
Number of nX5 0..1 arrays with every element equal to 0, 1, 2 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
16, 78, 79, 251, 896, 2669, 8283, 25770, 79047, 246053, 762945, 2360425, 7321295, 22685256, 70286966, 217858158, 675095417, 2092068068, 6483475187, 20091819256, 62264156028, 192956081997, 597964496726, 1853080152322, 5742656322238
OFFSET
1,1
COMMENTS
Column 5 of A302623.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +3*a(n-2) +6*a(n-3) -12*a(n-4) -6*a(n-5) -7*a(n-6) -4*a(n-7) +20*a(n-9) +30*a(n-10) +4*a(n-11) -19*a(n-12) -36*a(n-13) +4*a(n-14) +16*a(n-15) for n>20
EXAMPLE
Some solutions for n=5
..0..1..1..0..1. .0..1..1..0..1. .0..0..1..0..1. .0..0..1..0..1
..0..0..1..0..0. .0..0..1..1..1. .1..0..1..1..1. .1..0..1..0..1
..1..0..1..1..0. .1..0..1..0..1. .1..1..1..0..1. .1..1..1..1..1
..1..0..0..1..0. .1..1..1..0..0. .1..0..1..0..0. .1..0..1..0..1
..1..1..0..1..0. .1..0..1..1..0. .0..0..1..1..0. .1..0..1..0..0
CROSSREFS
Cf. A302623.
Sequence in context: A082966 A198182 A281466 * A195976 A302412 A303179
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 10 2018
STATUS
approved