OFFSET
1,2
COMMENTS
Column 3 of A202924.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (1/17280)*n^9 + (23/20160)*n^8 + (193/20160)*n^7 + (13/288)*n^6 + (523/5760)*n^5 + (1/2880)*n^4 + (29/4320)*n^3 + (457/1008)*n^2 + (11/28)*n.
Conjectures from Colin Barker, Jun 02 2018: (Start)
G.f.: x*(1 + 35*x^2 - 36*x^3 + 30*x^4 - 10*x^5 + x^6) / (1 - x)^10.
a(n) = 10*a(n-1) - 45*a(n-2) + 120*a(n-3) - 210*a(n-4) + 252*a(n-5) - 210*a(n-6) + 120*a(n-7) - 45*a(n-8) + 10*a(n-9) - a(n-10) for n>10.
(End)
EXAMPLE
Some solutions for n=5:
..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..2..2....0..1..1....0..0..1....0..0..2....0..0..2....0..0..2....0..0..1
..0..2..3....0..1..1....0..2..2....0..1..4....0..1..2....0..1..2....0..0..2
..0..3..6....0..3..3....0..3..5....0..3..5....0..1..2....0..1..2....0..0..2
..0..3..6....0..3..4....0..3..6....0..3..5....0..2..2....0..2..5....0..2..5
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 26 2011
STATUS
approved