A207196 - OEIS

%I #5 Mar 31 2012 12:37:15

%S 25,625,12534,247002,4841210,94815963,1858463962,36432515728,

%T 714296094954,14004808504521,274586566648434,5383711555276632,

%U 105556307341848307,2069600579240974133,40577832819063923601

%N Number of nX3 0..2 arrays avoiding the pattern z-1 z-1 z in any row or column

%C Column 3 of A207201

%H R. H. Hardin, <a href="/A207196/b207196.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 25*a(n-1) -48*a(n-2) -1468*a(n-3) +4228*a(n-4) +58087*a(n-5) -184932*a(n-6) -1165366*a(n-7) +3539838*a(n-8) +16449489*a(n-9) -43427901*a(n-10) -70826176*a(n-11) +249121716*a(n-12) +96296868*a(n-13) -861260208*a(n-14) -223911709*a(n-15) +2626398112*a(n-16) +898390509*a(n-17) -7420210932*a(n-18) -99776771*a(n-19) +15841428878*a(n-20) -1482004027*a(n-21) -27899116782*a(n-22) -2095158477*a(n-23) +49319804695*a(n-24) -6637061682*a(n-25) -69608869207*a(n-26) +25701110196*a(n-27) +66064467544*a(n-28) -11014179568*a(n-29) -64870125327*a(n-30) +14474720064*a(n-31) +71767151733*a(n-32) -58116210928*a(n-33) -42714615614*a(n-34) +51889023154*a(n-35) +6545107206*a(n-36) -18403480596*a(n-37) +2906099248*a(n-38) +1495371375*a(n-39) -2067527924*a(n-40) +1607739413*a(n-41) +223733829*a(n-42) -430305448*a(n-43) +52018089*a(n-44) +34503360*a(n-45) -21222282*a(n-46) +11329488*a(n-47) -549645*a(n-48) +244841*a(n-49) +124037*a(n-50) -98499*a(n-51) +17892*a(n-52) -5820*a(n-53) +240*a(n-54)

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 15 2012