OFFSET
1,2
COMMENTS
Column 4 of A211561
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = sum{j in 4..n+3}stirling2(n+3,j)
EXAMPLE
Some solutions for n=5
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....1....0....1....1....0....1....1....1....0....1....1....1....1....1....1
..0....0....0....2....2....1....2....2....1....1....2....2....1....2....2....0
..2....2....1....3....3....2....0....0....2....2....0....0....2....3....0....2
..0....1....2....0....1....0....3....2....2....2....3....0....3....2....3....3
..2....0....1....1....3....1....1....3....3....3....4....1....1....2....2....2
..3....2....3....4....4....0....0....2....0....0....2....0....2....1....3....0
..0....3....0....4....2....3....1....3....4....1....3....3....0....0....2....3
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 15 2012
STATUS
approved