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A232585
Number of (n+1)X(4+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
26, 152, 996, 6406, 41328, 266490, 1718514, 11082034, 71463916, 460844060, 2971811106, 19164098964, 123582110878, 796934839170, 5139134890906, 33140359949992, 213709793755260, 1378134577168966, 8887074754111400
OFFSET
1,1
COMMENTS
Column 4 of A232589
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) +9*a(n-2) +2*a(n-3) +a(n-4) +2*a(n-5).
Empirical: G.f.: -2*x*(13+11*x+x^2+3*x^3+2*x^4) / ( (1+x)*(2*x^4-x^3+3*x^2+6*x-1) ). - R. J. Mathar, Nov 23 2014
EXAMPLE
Some solutions for n=7
..0..1..0..1..0....0..1..0..1..0....0..1..0..1..0....0..1..0..1..0
..2..1..2..1..0....2..1..2..1..0....2..1..2..1..0....2..1..2..1..0
..2..1..0..1..2....0..1..2..1..2....0..1..2..1..0....0..1..2..1..0
..2..1..2..1..0....2..1..0..1..0....0..1..2..1..0....0..1..2..1..2
..0..1..0..1..2....2..1..0..1..2....2..1..0..1..0....0..1..2..1..0
..0..1..2..1..0....0..1..2..1..0....0..1..2..1..0....0..1..2..1..2
..2..1..2..1..2....0..1..2..1..0....0..1..2..1..2....0..1..2..1..0
..0..1..0..1..2....2..1..0..1..2....0..1..2..1..0....0..1..0..1..2
CROSSREFS
Sequence in context: A014552 A192289 A230906 * A042314 A280213 A200874
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 26 2013
STATUS
approved