OFFSET
1,1
COMMENTS
Row 2 of A212729
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
From Vaclav Kotesovec, Jul 31 2013: (Start)
Empirical: n*(2*n-1)*(816*n^3 - 5572*n^2 + 11983*n - 8097)*a(n) = (31008*n^5 - 250088*n^4 + 727230*n^3 - 936367*n^2 + 518859*n - 93600)*a(n-1) - 9*(17952*n^5 - 157672*n^4 + 514566*n^3 - 767531*n^2 + 504861*n - 106650)*a(n-2) + 81*(n-3)*(2*n-5)*(816*n^3 - 3124*n^2 + 3287*n - 870)*a(n-3).
Conjecture: a(n) ~ 3/2*9^n. (End)
EXAMPLE
Some solutions for n=3
..0....1....0....0....2....1....0....1....1....1....2....1....0....2....0....2
..0....0....0....1....0....2....1....2....0....1....0....0....1....0....1....1
..0....0....1....0....0....0....1....0....0....0....1....1....0....0....0....0
..2....1....1....1....2....1....2....2....0....1....0....1....0....2....1....0
..0....2....0....2....0....0....0....0....0....0....1....0....2....0....0....2
..0....0....1....0....1....1....0....0....1....1....1....2....2....0....2....0
..2....0....2....0....2....1....1....0....1....0....1....1....0....0....1....2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin May 25 2012
STATUS
approved