OFFSET
1,1
COMMENTS
Column 3 of A239849
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (1/6227020800)*n^13 - (1/119750400)*n^12 + (221/479001600)*n^11 - (103/10886400)*n^10 + (649/4838400)*n^9 + (3569/3628800)*n^8 - (2313347/43545600)*n^7 + (10192331/10886400)*n^6 - (87698557/10886400)*n^5 + (82688371/2721600)*n^4 + (101725069/1247400)*n^3 - (505121941/415800)*n^2 + (698568509/180180)*n - 2851 for n>9
EXAMPLE
Some solutions for n=4
..0..0..3....0..3..3....0..3..3....0..3..3....0..3..3....0..0..3....0..3..3
..0..3..3....0..3..3....0..3..3....3..1..3....0..3..2....0..0..3....3..1..2
..3..1..2....3..1..0....0..0..0....3..3..0....0..0..3....0..3..1....3..2..0
..3..2..0....3..2..0....3..1..0....0..2..1....0..0..3....3..3..2....0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 28 2014
STATUS
approved