A264956 - OEIS

%I #8 Apr 20 2021 19:10:59

%S 24,504,10728,269352,7340712,212706840,6427851432,200437195992,

%T 6401503898904,208353728741064,6885992401320264,230473529137180056,

%U 7796234052703001880,266117752529540837544,9154725401806039272072

%N Number of 4 X n arrays containing n copies of 0..4-1 with no equal horizontal or vertical neighbors.

%C Row 4 of A264954.

%H R. H. Hardin, <a href="/A264956/b264956.txt">Table of n, a(n) for n = 1..24</a>

%e Some solutions for n=3

%e ..0..1..2....3..2..3....2..1..2....1..3..1....2..1..3....2..3..0....0..2..3

%e ..3..2..1....2..0..1....3..2..0....0..1..0....3..0..1....3..2..1....1..0..1

%e ..1..3..0....1..3..2....0..3..1....3..2..3....2..3..0....0..1..3....3..2..0

%e ..2..0..3....0..1..0....3..1..0....2..0..2....1..0..2....2..0..1....2..1..3

%Y Cf. A264954.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 29 2015