OFFSET
1,1
COMMENTS
Column 1 of A204230
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 9*a(n-1) -2*a(n-2) -210*a(n-3) +498*a(n-4) +1782*a(n-5) -7500*a(n-6) -4716*a(n-7) +53007*a(n-8) -25623*a(n-9) -209346*a(n-10) +253710*a(n-11) +460144*a(n-12) -940824*a(n-13) -427120*a(n-14) +1906032*a(n-15) -338256*a(n-16) -2148336*a(n-17) +1287648*a(n-18) +1144800*a(n-19) -1233792*a(n-20) -62208*a(n-21) +414720*a(n-22) -124416*a(n-23)
EXAMPLE
Some solutions for n=4
..1..0....2..1....1..2....1..2....1..1....0..2....0..1....0..1....2..0....0..2
..0..1....0..2....2..1....2..2....0..0....2..0....2..0....2..0....0..1....1..2
..1..1....1..2....2..1....1..2....2..0....1..2....2..0....1..2....0..2....0..2
..0..2....2..1....2..2....2..2....0..2....1..2....2..2....2..0....1..2....2..1
..1..2....1..2....2..1....2..1....0..2....1..2....2..0....1..2....2..2....2..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 13 2012
STATUS
approved