OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-1) + 6*a(n-2) - 24*a(n-3) + 4*a(n-4) + 36*a(n-5) - 24*a(n-6).
Empirical g.f.: 2*x*(122 - 187*x - 989*x^2 + 1508*x^3 + 1554*x^4 - 2268*x^5) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 6*x^2)). - Colin Barker, Oct 14 2018
EXAMPLE
Some solutions for n=5:
2 2 0 0 0 0 0 0 0 0 0 2 0 2 0 2 2 1 0 0
2 0 0 2 0 2 0 2 0 2 0 0 0 0 0 2 0 1 2 0
2 2 0 0 0 0 0 0 0 0 0 2 0 2 0 2 2 1 0 0
2 0 0 2 0 2 0 2 0 2 1 1 1 1 1 2 0 1 2 0
2 2 0 0 0 2 2 2 2 2 2 0 2 0 2 2 2 1 0 0
2 0 0 2 0 2 0 2 0 2 2 2 2 2 2 2 0 1 2 0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 22 2013
STATUS
approved