OFFSET
1,1
COMMENTS
Row 6 of A255992.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (1/6)*n^3 + 3*n^2 + (533/6)*n + 28 for n>4.
Empirical g.f.: x*(128 - 256*x + 98*x^2 + 59*x^3 - 8*x^4 - 21*x^5 - 8*x^6 + 9*x^7) / (1 - x)^4. - Colin Barker, Jan 26 2018
EXAMPLE
Some solutions for n=4:
..0....0....0....1....1....0....1....0....1....1....1....0....1....0....0....0
..1....1....0....1....1....1....1....1....0....1....0....1....0....0....0....0
..0....0....0....0....0....0....1....0....0....0....0....1....0....1....1....0
..0....0....1....0....0....0....1....0....0....0....0....0....0....1....1....0
..1....1....0....0....0....1....1....1....1....0....0....0....0....0....0....0
..1....1....0....0....0....1....1....1....1....0....1....0....0....0....0....1
..0....0....0....0....0....1....1....1....1....0....0....1....1....0....1....1
..1....0....0....0....0....1....0....0....1....1....1....1....1....1....1....1
..1....1....0....0....0....1....1....0....1....1....1....0....0....1....0....1
..1....1....0....1....0....1....1....0....0....1....1....0....1....0....1....0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 13 2015
STATUS
approved