OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 24*a(n-1) - 224*a(n-2) + 1096*a(n-3) - 3360*a(n-4) + 6976*a(n-5) - 9744*a(n-6) + 8704*a(n-7) - 4096*a(n-8) for n > 9.
Empirical g.f.: 2*x*(3 + 52*x - 640*x^2 + 2610*x^3 - 6024*x^4 + 7944*x^5 - 2824*x^6 - 4736*x^7 + 10240*x^8) / (1 - 12*x + 40*x^2 - 68*x^3 + 64*x^4)^2. - Colin Barker, Sep 18 2018
EXAMPLE
Some solutions for n=4:
0 1 0 2 0 1 2 3 0 1 2 0 0 1 2 3 0 1 2 3
0 3 1 3 3 0 0 1 2 3 1 3 3 0 1 3 2 3 1 2
1 0 2 0 2 1 3 2 0 2 0 2 2 3 0 2 1 2 1 0
3 1 3 2 0 2 1 0 1 3 2 1 0 2 3 1 3 0 3 2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 24 2013
STATUS
approved