A209857 - OEIS

%I #7 May 28 2021 12:37:15

%S 3553425,2383064182,1538049629157,1014683000461958,665390868679472699,

%T 437706800031436404447,287490532338602681041344,

%U 188980762791958451221301355,124172412194974480096912519039

%N 1/4 the number of (n+1) X 8 0..3 arrays with every 2 X 2 subblock having one or four distinct clockwise edge differences.

%C Column 7 of A209858.

%H R. H. Hardin, <a href="/A209857/b209857.txt">Table of n, a(n) for n = 1..164</a>

%e Some solutions for n=4

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

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

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

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

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

%Y Cf. A209858.

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 14 2012