OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-1) +13*a(n-2) -43*a(n-3) -67*a(n-4) +254*a(n-5) +171*a(n-6) -797*a(n-7) -213*a(n-8) +1427*a(n-9) +85*a(n-10) -1458*a(n-11) +60*a(n-12) +810*a(n-13) -58*a(n-14) -224*a(n-15) +12*a(n-16) +24*a(n-17)
EXAMPLE
Some solutions for n=5
..0....0....3....0...-1....2...-2...-3...-1...-3....2...-3...-3...-1...-1....1
.-1....1...-1....1...-1....2...-3....1...-3....1...-2...-2....3....0...-1....0
.-2...-3....1....0....1....2...-2....1...-1...-3....2...-1....3...-1....3...-1
.-1....1...-1...-2....3....2...-1...-3....3....1...-2...-2....3....0...-1....0
..0....0...-1....0....1...-2....0....1...-1...-2....2...-1....3...-1....3...-1
.-1...-2...-1...-2....3....2....1...-3....2....1....0...-2...-3....0...-1...-2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 13 2012
STATUS
approved