OFFSET
1,1
COMMENTS
Column 1 of A237904
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 1784*a(n-4) +39800*a(n-6) +151364*a(n-8) -3049440*a(n-10) -26111208*a(n-12) +14962784*a(n-14) +687231488*a(n-16) +1360519984*a(n-18) -4184091008*a(n-20) -12843568640*a(n-22) +1638036736*a(n-24) +9279855360*a(n-26) -23629565952*a(n-28) +19040813056*a(n-30) +44134580224*a(n-32) -27197440000*a(n-34) -25461784576*a(n-36) +7525629952*a(n-38) +2793406464*a(n-40) for n>41
EXAMPLE
Some solutions for n=4
..0..1....2..0....1..1....2..1....3..3....0..0....1..0....3..0....0..2....0..3
..2..0....3..0....3..1....0..3....3..2....3..2....0..3....0..3....1..3....2..0
..0..2....0..3....1..2....1..0....2..0....3..2....0..0....1..2....3..0....1..2
..1..1....2..0....0..1....2..3....2..2....2..2....2..2....2..3....2..0....2..2
..0..1....0..2....1..1....1..1....0..3....1..3....2..3....2..2....1..2....3..3
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 15 2014
STATUS
approved