OFFSET
1,4
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..115
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-4) -2*a(n-5) -a(n-8) +a(n-9) +a(n-16) -a(n-18) -2*a(n-20) +2*a(n-22) +a(n-24) -a(n-26) -a(n-33) +a(n-34) +2*a(n-37) -2*a(n-38) -a(n-41) +a(n-42)
EXAMPLE
Some solutions for n=4
..2..0....4..0....2..4....1..0....0..0....1..4....4..4....0..4....4..3....3..4
..1..0....3..0....1..4....0..0....0..1....1..0....0..4....0..0....0..3....2..4
..2..4....4..4....2..0....1..4....4..0....2..4....4..3....1..4....4..2....3..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 29 2011
STATUS
approved