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A209507
Half the number of (n+1) X 5 0..2 arrays with every 2 X 2 subblock having two or four distinct clockwise edge differences.
1
243, 2559, 27225, 290493, 3102219, 33137271, 353991129, 3781613733, 40398442707, 431571603279, 4610428863921, 49252678808493, 526160699942619, 5620914282594855, 60047581462986825, 641481414281948277
OFFSET
1,1
COMMENTS
Column 4 of A209511.
LINKS
FORMULA
Empirical: a(n) = 16*a(n-1) - 65*a(n-2) + 92*a(n-3) - 48*a(n-4) + 8*a(n-5).
Empirical g.f.: 3*x*(81 - 443*x + 692*x^2 - 376*x^3 + 64*x^4) / (1 - 16*x + 65*x^2 - 92*x^3 + 48*x^4 - 8*x^5). - Colin Barker, Jul 10 2018
EXAMPLE
Some solutions for n=4:
..2..0..1..2..0....0..1..0..2..1....0..1..2..0..1....0..1..0..1..0
..0..2..0..1..2....2..0..1..0..2....1..2..0..1..2....1..2..1..2..1
..2..0..1..2..0....0..2..0..1..0....2..1..2..0..1....2..1..2..1..2
..0..2..0..1..2....2..0..2..0..1....1..0..1..2..0....1..0..1..2..0
..1..0..1..2..0....1..2..0..2..0....0..2..0..1..2....2..1..2..1..2
CROSSREFS
Cf. A209511.
Sequence in context: A233158 A100627 A269056 * A226777 A016757 A133550
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 09 2012
STATUS
approved