OFFSET
1,1
COMMENTS
Column 5 of A252876.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (1/259200)*n^10 + (1/6480)*n^9 + (149/60480)*n^8 + (163/7560)*n^7 + (10411/86400)*n^6 + (1027/2160)*n^5 + (16357/12960)*n^4 + (937/810)*n^3 + (1756/1575)*n^2 - (727/630)*n + 3.
Empirical: G.f.: -x*(6 -5*x +72*x^2 -225*x^3 +460*x^4 -612*x^5 +537*x^6 -315*x^7 +121*x^8 -28*x^9 +3*x^10) / (x-1)^11. - R. J. Mathar, Nov 21 2015
EXAMPLE
Some solutions for n=3:
..0..1..2..3..4....0..0..0..1..2....0..1..1..1..2....0..0..1..1..2
..1..2..2..3..4....0..0..1..2..3....0..1..2..2..3....1..1..1..2..3
..2..3..3..4..4....0..1..2..3..4....1..2..3..3..4....1..1..2..3..4
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 24 2014
STATUS
approved