OFFSET
1,4
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..100
EXAMPLE
All solutions for n=6:
..0...-1...-1...-1
..0....0...-1....0
..0....0....0....0
..0....1....1....0
..0....0....1....1
..0....0....0....0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 04 2012
EXTENSIONS
a(33)-a(36) from Andrew Howroyd, Mar 19 2017
STATUS
approved