OFFSET
1,1
COMMENTS
Row 4 of A212835.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = n^5 + 5*n^4 + 2*n^3 - 8*n^2 + n + 1.
Conjectures from Colin Barker, Jul 21 2018: (Start)
G.f.: x*(2 + 87*x + 70*x^2 - 50*x^3 + 12*x^4 - x^5) / (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=5:
..5....5....3....3....1....2....5....5....4....0....5....5....0....1....2....2
..4....2....3....2....4....2....1....5....1....2....3....3....3....2....2....4
..5....3....5....0....3....1....3....4....5....5....1....1....1....4....1....0
..2....1....4....2....0....2....4....3....3....3....5....3....5....1....5....4
..4....5....1....4....1....0....4....4....2....4....5....1....3....0....2....0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 28 2012
STATUS
approved