OFFSET
1,2
COMMENTS
Column 5 of A221381
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..48
FORMULA
Empirical: a(n) = 42*a(n-2) -497*a(n-4) +2546*a(n-6) -6335*a(n-8) +7910*a(n-10) -5003*a(n-12) +1526*a(n-14) -196*a(n-16) +8*a(n-18)
EXAMPLE
Some solutions for n=4
..0..2..2..2..0....0..2..2..2..0....0..2..2..2..0....0..2..2..2..0
..0..0..0..2..0....0..0..0..0..2....0..0..0..2..2....0..0..2..2..2
..2..2..2..2..2....2..2..0..2..0....2..2..0..0..0....0..2..0..0..0
..0..0..0..2..0....0..2..2..2..0....0..2..2..2..0....0..2..2..2..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 14 2013
STATUS
approved