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A295777
Number of nX4 0..1 arrays with each 1 adjacent to 0 or 2 king-move neighboring 1s.
1
8, 49, 198, 1059, 5263, 25529, 127731, 630988, 3118368, 15452696, 76444609, 378316752, 1872559828, 9266918261, 45863407707, 226985095214, 1123365612319, 5559672436516, 27515436853783, 136176807358073, 673954171761877
OFFSET
1,1
COMMENTS
Column 4 of A295781.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +6*a(n-2) +6*a(n-3) -58*a(n-4) -20*a(n-5) +29*a(n-6) -92*a(n-7) +7*a(n-8) +2*a(n-9) -2*a(n-10)
EXAMPLE
Some solutions for n=7
..0..0..0..0. .0..0..0..1. .0..0..1..1. .0..0..1..0. .0..0..0..1
..0..1..0..0. .0..0..0..0. .1..0..1..0. .1..0..0..0. .1..1..0..0
..1..1..0..0. .1..0..0..0. .0..0..0..0. .0..0..1..0. .0..1..0..1
..0..0..0..0. .0..0..0..1. .0..0..0..1. .0..1..1..0. .0..0..0..0
..0..0..0..1. .0..1..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..0
..1..1..0..0. .0..0..0..0. .1..1..0..1. .0..1..0..0. .0..0..0..0
..1..0..0..0. .1..0..0..0. .0..1..0..0. .1..1..0..1. .1..0..1..0
CROSSREFS
Cf. A295781.
Sequence in context: A306049 A317226 A329051 * A319959 A270007 A354558
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 27 2017
STATUS
approved