OFFSET
1,1
COMMENTS
Column 4 of A253407
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 160*a(n-3) -7952*a(n-6) +98358*a(n-9) +1917280*a(n-12) -53187384*a(n-15) -68774113*a(n-18) +7983927856*a(n-21) -4682894632*a(n-24) -687025828328*a(n-27) -4013350970720*a(n-30) -4983960145280*a(n-33) +22542564452080*a(n-36) +57373712662592*a(n-39) -74581831759040*a(n-42) -225211762413056*a(n-45) +204280702855424*a(n-48) +329790587612160*a(n-51) -337058300150784*a(n-54) -25034074472448*a(n-57) -449521975296*a(n-60) for n>69
EXAMPLE
Some solutions for n=3
..2..1..2..0..1....2..2..0..1..0....0..1..2..2..2....0..0..0..2..2
..2..0..0..1..2....2..1..0..0..1....0..0..0..2..1....0..1..0..2..0
..0..1..0..1..0....2..2..1..2..2....1..2..0..1..1....1..1..1..2..1
..0..1..2..2..0....2..2..0..0..1....2..1..0..0..0....2..2..0..1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 31 2014
STATUS
approved