OFFSET
1,2
COMMENTS
Column 1 of A193702
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 2*a(n-1) +a(n-2) +a(n-4) +a(n-5).
Empirical: G.f.: x*( -1-x-2*x^2-2*x^3-x^4 ) / ( -1+2*x+x^2+x^4+x^5 ). - R. J. Mathar, Feb 19 2015
EXAMPLE
Some solutions for n=6
.-1....0....1....0....0....0....0....0....1...-1....1....1....0....1...-1....0
..1...-1...-1....0....0....0...-1....1...-1....1...-1...-1....0...-1....1...-1
..0....1....1....0....1....0....0...-1....0....1....1....1....1....1...-1....1
..0....0....1....1....0...-1....1....0....0...-1...-1....0...-1...-1....0...-1
..1...-1...-1...-1...-1....1....1....0....1....0....1....0....0....0....1....1
.-1....0....0....1....1....0...-1....0...-1....0...-1....0....0....1...-1....0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 02 2011
STATUS
approved