OFFSET
1,3
COMMENTS
Column 3 of A194480.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = (1/48)*n^6 + (1/16)*n^5 - (3/16)*n^4 + (1/48)*n^3 + (1/6)*n^2 - (1/12)*n.
Empirical g.f.: x^2*(1 + 10*x + 7*x^2 - 3*x^3) / (1 - x)^7. - Colin Barker, May 05 2018
EXAMPLE
The 17 solutions for 3 X 3 X 3:
.
1 1 1 1 1 1
1 1 1 0 1 0 0 1 0 1 0 0
0 0 0 0 1 0 0 0 1 1 0 0 0 1 0 1 1 0
1 1 0 0 0
0 0 0 0 1 1 1 1 1 1
1 0 1 0 1 1 1 0 0 0 1 0 0 0 1
0 0 0 0 0 0
1 0 1 0 1 0 0 1 0 1 0 1
1 1 0 1 0 1 0 1 1 1 1 0 1 0 1 0 1 1
[edited by Jon E. Schoenfield, May 05 2018]
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 26 2011
STATUS
approved