cp's OEIS Frontend

A233161 Number of n X n 0..7 arrays with no element x(i,j) adjacent to itself or value 7-x(i,j) horizontally, diagonally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 4 5 and 6, 2 appearing before 3 4 and 5, and 3 appearing before 4 in row major order (unlabelled 8-colorings with no clashing color pairs).

%I A233161 #8 Jun 02 2025 08:51:17
%S A233161 1,1,96,28672,31457280,133143986176,2216615441596416,
%T A233161 146421031085069565952,38534510500216304943759360,
%U A233161 40485591044789076510300958621696
%N A233161 Number of n X n 0..7 arrays with no element x(i,j) adjacent to itself or value 7-x(i,j) horizontally, diagonally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 4 5 and 6, 2 appearing before 3 4 and 5, and 3 appearing before 4 in row major order (unlabelled 8-colorings with no clashing color pairs).
%C A233161 Diagonal of A233168
%H A233161 R. H. Hardin, <a href="/A233161/b233161.txt">Table of n, a(n) for n = 1..16</a>
%e A233161 Some solutions for n=4
%e A233161 ..0..1..0..2....0..1..2..1....0..1..2..1....0..1..7..1....0..1..2..6
%e A233161 ..3..5..3..6....5..3..7..3....5..3..0..3....2..3..5..3....5..3..0..4
%e A233161 ..0..6..0..2....0..6..5..6....0..6..2..1....1..7..6..7....7..6..5..1
%e A233161 ..4..2..3..6....2..4..7..3....5..3..0..4....4..5..3..5....5..4..7..3
%K A233161 nonn
%O A233161 1,3
%A A233161 _R. H. Hardin_, Dec 05 2013