OFFSET
1,1
COMMENTS
Column 3 of A240338
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (1/1556755200)*n^13 + (13/479001600)*n^12 + (709/239500800)*n^11 - (1097/43545600)*n^10 + (4523/2419200)*n^9 - (600197/14515200)*n^8 + (21519737/21772800)*n^7 - (738857411/43545600)*n^6 + (5266122739/21772800)*n^5 - (29277165523/10886400)*n^4 + (450145058857/19958400)*n^3 - (224785067849/1663200)*n^2 + (23586754661/45045)*n - 987842 for n>12
EXAMPLE
Some solutions for n=4
..0..3..0....0..0..0....3..0..0....0..0..0....0..0..3....0..0..3....0..0..3
..0..0..3....0..0..0....0..3..0....0..3..0....3..0..3....3..0..3....0..0..3
..0..3..0....0..3..3....3..3..1....0..0..3....0..3..3....3..3..3....0..3..2
..3..2..2....0..0..3....3..2..2....0..0..3....3..3..2....3..3..2....3..3..3
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 04 2014
STATUS
approved