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A232517
Number of (2+1)X(n+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally, diagonally or antidiagonally, with no adjacent elements equal
1
4, 52, 32, 326, 250, 2138, 1956, 13976, 14782, 91760, 109522, 604450, 799026, 3994420, 5761416, 26475334, 41161880, 175967762, 291918330, 1172568978, 2057927044, 7831923864, 14436579566, 52424836208, 100861979186, 351610320834
OFFSET
1,1
COMMENTS
Row 2 of A232515
LINKS
FORMULA
Empirical: a(n) = 6*a(n-2) +a(n-3) +3*a(n-4) +a(n-5) -2*a(n-6) -2*a(n-7).
Empirical: G.f.: -2*x*(-2-26*x-4*x^2-5*x^3+3*x^4+5*x^5+5*x^6) / ( 1-6*x^2-x^3-3*x^4-x^5+2*x^6+2*x^7 ). - R. J. Mathar, Nov 23 2014
EXAMPLE
Some solutions for n=7
..1..0..1..0..1..0..1..0....0..1..2..0..1..2..1..2....2..1..0..1..2..1..2..1
..1..2..1..2..1..2..1..0....2..1..2..0..1..2..1..0....2..1..0..1..2..1..0..1
..1..0..1..0..1..2..1..2....0..1..2..0..1..2..1..0....0..1..0..1..2..1..2..1
CROSSREFS
Sequence in context: A182044 A000854 A377382 * A329009 A110908 A232507
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 25 2013
STATUS
approved