OFFSET
1,1
COMMENTS
Column 5 of A267471.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 26*a(n-1) -280*a(n-2) +1610*a(n-3) -5299*a(n-4) +9884*a(n-5) -9540*a(n-6) +3600*a(n-7).
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: x*(6 - 120*x + 945*x^2 - 3710*x^3 + 7539*x^4 - 7336*x^5 + 2556*x^6) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)^2*(1 - 6*x)).
a(n) = (-75 - 25*2^(1+n) - 50*3^n + 25*2^(1+n)*3^n - 75*4^n + 413*5^n + 12*5^n*n) / 300.
(End)
EXAMPLE
Some solutions for n=7:
..2....1....0....4....3....5....2....0....3....3....4....4....0....4....1....3
..0....3....3....1....1....0....0....4....0....3....3....3....3....4....4....1
..4....2....4....2....2....1....4....1....3....1....0....5....1....0....5....2
..0....4....1....3....0....5....0....5....0....0....3....1....2....0....2....1
..3....0....5....2....4....4....2....0....3....0....2....0....5....3....0....4
..4....2....3....2....4....1....5....4....2....3....0....1....5....2....4....3
..0....4....0....1....0....3....2....3....1....2....3....0....4....1....4....5
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 15 2016
STATUS
approved