OFFSET
1,1
COMMENTS
Column 7 of A212835.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 7*a(n-1) + 6*a(n-2).
Empirical g.f.: 2*x*(31 + 24*x) / (1 - 7*x - 6*x^2). - Colin Barker, Jul 21 2018
EXAMPLE
Some solutions for n=5:
..4....4....2....6....2....4....0....2....4....2....2....0....2....4....2....4
..3....1....2....4....1....0....0....1....6....4....7....5....7....2....5....0
..3....2....0....7....7....2....3....1....0....3....2....6....7....5....2....3
..5....1....1....4....2....6....7....2....3....5....6....1....1....7....1....2
..0....1....6....6....4....4....6....3....2....6....3....5....2....1....4....7
..2....0....2....4....0....3....2....4....2....1....1....3....4....5....5....5
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 28 2012
STATUS
approved