|
%I #5 Mar 31 2012 12:35:52
%S 27,776,19683,531441,14369472,387420489,10460353203,282432195144,
%T 7625597484987,205891132094649,5559061744716480,150094635296999121,
%U 4052555153018976267,109418989288418720136,2954312706550833698643
%N Number of nX3 0..3 arrays with no element equal to the sum mod 4 of its horizontal and vertical neighbors
%C Column 3 of A183508
%H R. H. Hardin, <a href="/A183505/b183505.txt">Table of n, a(n) for n = 1..180</a>
%F Empirical: a(n)=27*a(n-1)+63909*a(n-6)-1725543*a(n-7)-274577850*a(n-12)+7413601950*a(n-13)-739973133990*a(n-18)+19979274617730*a(n-19)+454993983270891*a(n-24)-12284837548314057*a(n-25)+150094635296999121*a(n-30)-4052555153018976267*a(n-31)
%e Some solutions for 5X3
%e ..0..2..2....0..0..0....0..0..0....0..0..0....2..0..0....2..2..2....0..0..2
%e ..0..2..2....2..2..2....3..2..2....3..2..2....0..0..2....2..0..2....1..0..0
%e ..1..1..3....2..1..3....2..0..3....2..2..3....0..3..1....2..0..3....2..2..1
%e ..3..1..2....0..0..2....1..0..3....0..0..0....0..0..2....1..0..2....2..1..2
%e ..2..1..1....3..2..2....2..2..2....3..0..3....2..0..0....0..2..1....1..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 05 2011
| 