OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = n^5 + (37/12)*n^4 + (5/2)*n^3 + (5/12)*n^2.
Conjectures from Colin Barker, Jan 10 2019: (Start)
G.f.: x*(7 + 61*x + 51*x^2 + x^3) / (1 - x)^6.
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
(End)
EXAMPLE
Some solutions for n=6:
..3....6....4....4....0....0....4....6....5....5....5....0....2....0....4....0
..2....6....2....1....4....5....1....0....4....0....1....3....5....1....1....2
..1....2....3....6....3....1....6....3....0....1....4....6....6....6....0....1
..6....1....6....6....6....3....3....4....4....0....5....3....4....5....1....3
..0....4....6....5....5....1....4....6....5....5....6....5....4....4....1....4
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 12 2016
STATUS
approved