OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 6*a(n-1) +11*a(n-2) -127*a(n-3) +27*a(n-4) +1183*a(n-5) -1132*a(n-6) -6381*a(n-7) +8929*a(n-8) +22055*a(n-9) -38648*a(n-10) -51000*a(n-11) +107487*a(n-12) +79800*a(n-13) -203031*a(n-14) -83121*a(n-15) +265573*a(n-16) +54369*a(n-17) -240368*a(n-18) -18623*a(n-19) +148011*a(n-20) +317*a(n-21) -59912*a(n-22) +2112*a(n-23) +15014*a(n-24) -650*a(n-25) -2080*a(n-26) +60*a(n-27) +120*a(n-28)
EXAMPLE
Some solutions for n=5
..1....0...-1....3....4...-1....1....0....4....2...-3....1....1....2...-1....4
.-1...-2....0...-1....0....1....0....0....0....1....2....0...-1...-2...-3...-4
..0....2....1....0....4...-1...-2....3....0....0...-3....1....1....0...-1...-4
..0...-2...-1...-1....0....1....2....0....0....1....2....0...-1....0....1...-4
..2....2....0....0....4...-1...-2....0...-2....2...-3...-2....1....0...-1....4
..0....0....1....2...-2....0....0...-3....0....3...-1....2...-3....2...-3....4
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 18 2012
STATUS
approved