OFFSET
1,1
COMMENTS
Row 6 of A221542.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 1*n^5 + 2*n^4 - 6*n^3 + 21*n^2 - 31*n + 23 for n>4.
Conjectures from Colin Barker, Aug 08 2018: (Start)
G.f.: x*(5 + 24*x + 115*x^2 - 88*x^3 + 157*x^4 - 153*x^5 + 87*x^6 - 34*x^7 + 8*x^8 - x^9) / (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>10.
(End)
EXAMPLE
Some solutions for n=6:
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....5....0....5....0....2....0....5....0....6....5....3....0....4....2....2
..5....6....4....1....1....0....3....1....5....6....2....1....4....0....0....1
..1....4....6....0....6....1....4....6....4....1....2....3....2....6....4....3
..4....4....3....4....6....4....0....4....4....2....1....6....3....5....6....0
..2....4....1....1....3....0....4....6....2....0....3....6....5....0....2....6
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 19 2013
STATUS
approved