A269507 - OEIS

%I #6 Aug 12 2016 06:54:17

%S 4,54,420,3088,25226,239994,2338286,23240168,232006814,2352889414,

%T 24069853302,248560741574,2582277394354,26997628173380,

%U 283652378887212,2994183763030920,31727834772912212,337396544704648686

%N Number of 3Xn arrays containing n copies of 0..3-1 avoiding the pattern down-up in every row and column.

%C Row 3 of A269505.

%H R. H. Hardin, <a href="/A269507/b269507.txt">Table of n, a(n) for n = 1..48</a>

%e Some solutions for n=4

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

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

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

%Y Cf. A269505.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 28 2016