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A282643
Number of nX4 0..1 arrays with no 1 equal to more than one of its king-move neighbors.
1
13, 76, 413, 2638, 15460, 92817, 557439, 3332685, 19979228, 119669673, 716821452, 4294298464, 25723862625, 154096718455, 923100717695, 5529722705330, 33125219903271, 198432924637760, 1188690440868116, 7120718914489889
OFFSET
1,1
COMMENTS
Column 4 of A282647.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +16*a(n-2) +45*a(n-3) +16*a(n-4) -2*a(n-5) -51*a(n-6) -35*a(n-7) -23*a(n-8) +7*a(n-9).
Empirical: G.f.: -x*(13+50*x+53*x^2+11*x^3-52*x^4-86*x^5-58*x^6-16*x^7+7*x^8) /(-1+2*x+16*x^2+45*x^3+16*x^4-2*x^5-51*x^6-35*x^7-23*x^8+7*x^9) . - R. J. Mathar, Mar 02 2017
EXAMPLE
Some solutions for n=4
..0..0..0..0. .0..0..1..0. .0..0..1..0. .1..0..1..1. .0..1..0..1
..0..0..0..1. .0..1..0..0. .0..0..0..1. .0..0..0..0. .1..0..0..1
..1..0..0..0. .0..0..0..0. .1..0..0..0. .0..0..0..0. .0..0..0..0
..1..0..1..1. .1..0..1..0. .0..1..0..0. .0..1..0..0. .0..1..1..0
CROSSREFS
Cf. A282647.
Sequence in context: A114244 A050485 A034265 * A269085 A182077 A269071
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 20 2017
STATUS
approved