OFFSET
1,2
COMMENTS
Column 7 of A193648
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 2*a(n-1) +12*a(n-2) +a(n-3).
Empirical: G.f.: -x*(1+13*x+x^2) / ( -1+2*x+12*x^2+x^3 ). - R. J. Mathar, Feb 19 2015
EXAMPLE
Some solutions for n=6
.-1...-3....3....5....7....5....6....0....1....0...-5...-3...-7....1...-4....0
..1....3...-3...-5...-7...-5...-6....0...-1....7....5....3....7...-1....4....2
.-4....4....0...-3....0....2....6....7....0...-7...-5...-6...-7....4...-6...-2
..4...-4....0....3...-2...-2...-6...-7....0....0....6....6....7...-4....6....6
.-4....3...-1...-7....2....0....7...-3....6....3...-6...-7...-4...-2....3...-6
..4...-3....1....7...-2....0...-7....3...-6...-3....6....7....4....2...-3....0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 02 2011
STATUS
approved