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A232590
Number of (1+1)X(n+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or antidiagonally, with no adjacent elements equal
1
0, 10, 2, 26, 20, 70, 90, 210, 336, 674, 1178, 2234, 4036, 7502, 13714, 25314, 46464, 85562, 157266, 289370, 532116, 978838, 1800234, 3311282, 6090256, 11201874, 20603306, 37895546, 69700612, 128199582, 235795618, 433695938, 797691008
OFFSET
1,2
COMMENTS
Row 1 of A232589
LINKS
FORMULA
Empirical: a(n) = -a(n-1) +2*a(n-2) +4*a(n-3) +3*a(n-4) +a(n-5).
Empirical: G.f.: -2*x^2*(5+6*x+4*x^2+x^3) / ( (x^3+x^2+x-1)*(1+x)^2 ). - R. J. Mathar, Nov 23 2014
EXAMPLE
Some solutions for n=7
..0..1..2..1..0..1..2..0....0..1..2..1..2..1..0..2....0..1..2..1..2..0..1..2
..2..1..0..1..2..0..1..2....0..1..0..1..0..2..1..0....2..1..0..1..2..0..1..0
CROSSREFS
Sequence in context: A086068 A262557 A030595 * A094715 A213555 A305995
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 26 2013
STATUS
approved