%I #9 Mar 09 2018 10:21:19
%S 1,1,4,11,41,162,715,3424,17686,97493,567986,3462537,21880951,
%T 142148644,942800317,6349172750,43233294236,296737912815,
%U 2048310985708,14196341292463,98674810415941,687263739609206,4793697038780159
%N Number of 0..7 colorings of a 1 X (n+1) array circular in the n+1 direction with new values 0..7 introduced in row major order.
%C Row 1 of A214238.
%H R. H. Hardin, <a href="/A214239/b214239.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 21*a(n-1) - 168*a(n-2) + 630*a(n-3) - 1029*a(n-4) + 189*a(n-5) + 1198*a(n-6) - 840*a(n-7).
%F Empirical g.f.: x*(1 - 20*x + 151*x^2 - 535*x^3 + 881*x^4 - 531*x^5) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 7*x)).- _Colin Barker_, Mar 09 2018
%e Some solutions for n=4:
%e ..0..1..2..1..2.....0..1..0..2..1.....0..1..0..1..2.....0..1..2..3..1
%Y Cf. A214238.
%K nonn
%O 1,3
%A _R. H. Hardin_, Jul 08 2012