A267977 - OEIS

%I #4 Jan 23 2016 10:04:08

%S 60,3600,216000,12067722,648144348,33600202086,1691726672094,

%T 83078866656672,3993019853352132,188338933978296900,

%U 8737015871231173194,399355062781386269430,18013039522804400997948,802791844156171633174662

%N Number of 3Xn 0..3 arrays with every repeated value in every row greater than or equal to, and in every column greater than, the previous repeated value.

%C Row 3 of A267974.

%H R. H. Hardin, <a href="/A267977/b267977.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=2

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

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

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

%Y Cf. A267974.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 23 2016