|
%I #7 Sep 19 2018 08:51:01
%S 246,1312,1584,2064,2852,4048,6108,9992,17716,33504,66188,134200,
%T 275940,571280,1186108,2464488,5119124,10624576,22028268,45621656,
%U 94380868,195044592,402663068,830482504,1711286772,3523226528,7247768908
%N Number of defective 4-colorings of an n X 7 0..3 array connected horizontally, vertically, diagonally and antidiagonally with exactly one mistake, and colors introduced in row-major 0..3 order.
%H R. H. Hardin, <a href="/A229577/b229577.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) - 13*a(n-2) + 12*a(n-3) - 4*a(n-4) for n>7.
%F Empirical g.f.: 2*x*(123 - 82*x - 1545*x^2 + 3332*x^3 - 1850*x^4 + 4*x^5 + 232*x^6) / ((1 - x)^2*(1 - 2*x)^2). - _Colin Barker_, Sep 19 2018
%e Some solutions for n=3:
%e ..0..1..2..1..2..1..0....0..1..0..2..3..1..0....0..1..2..1..2..1..2
%e ..3..3..0..3..0..3..2....3..2..3..1..0..2..3....0..3..0..3..0..3..0
%e ..2..1..2..1..2..1..0....0..1..0..2..3..2..0....2..1..2..1..2..1..2
%Y Column 7 of A229578.
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 26 2013
|
