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A299874
Number of n X 3 0..1 arrays with every element equal to 0, 1, 2, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.
1
4, 13, 20, 41, 102, 253, 632, 1563, 3896, 9791, 24572, 61631, 154742, 388577, 975708, 2450385, 6154002, 15455231, 38815904, 97487349, 244842342, 614933595, 1544442076, 3878963103, 9742282792, 24468455765, 61454383034, 154347516727
OFFSET
1,1
COMMENTS
Column 3 of A299879.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -7*a(n-2) +7*a(n-3) -24*a(n-4) +31*a(n-5) -21*a(n-6) +51*a(n-7) -50*a(n-8) +44*a(n-9) -78*a(n-10) +34*a(n-11) -37*a(n-12) +60*a(n-13) -10*a(n-14) +20*a(n-15) -24*a(n-16) for n>17.
EXAMPLE
Some solutions for n=5
..0..1..0. .0..1..1. .0..0..1. .0..1..0. .0..0..0. .0..1..0. .0..1..0
..0..0..0. .1..0..0. .1..0..1. .0..0..0. .0..1..0. .1..0..0. .1..0..1
..0..0..0. .0..1..0. .0..1..0. .1..1..1. .0..0..0. .1..0..0. .1..0..0
..0..1..0. .1..0..0. .1..0..1. .0..0..0. .1..1..1. .1..0..0. .1..0..0
..0..0..0. .0..1..1. .0..0..1. .0..1..0. .1..0..1. .1..0..1. .0..1..0
CROSSREFS
Cf. A299879.
Sequence in context: A295159 A298216 A299092 * A299010 A299801 A299677
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 21 2018
STATUS
approved