OFFSET
1,1
COMMENTS
Column 5 of A190041.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 12*n - 27 for n>4.
Empirical: G.f.: x*(8 - 4*x + 3*x^3 + 3*x^4 + 2*x^5) / (1 - x)^2. a(n) = 2*a(n-1) - a(n-2) for n>2. - Colin Barker, May 04 2018
EXAMPLE
All solutions for n=3:
..5....1....2....1....1....4....1....0....1....1....1....2....3....2....1....1
..5....5....3....2....2....5....2....5....4....3....2....3....5....5....1....4
..5....5....5....3....3....5....3....5....4....4....2....3....5....5....2....5
..5....5....5....3....4....5....5....5....5....5....3....5....5....5....3....5
..5....5....5....5....5....5....5....5....5....5....5....5....5....5....5....5
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 04 2011
STATUS
approved