cp's OEIS Frontend

A185567 T(n,k)=1/4 the number of nXk 0..3 arrays with no element equal both to the element above and to the element to its left.

%I A185567 #7 Jul 22 2025 09:55:20
%S A185567 1,4,4,16,60,16,64,900,900,64,256,13500,50580,13500,256,1024,202500,
%T A185567 2842560,2842560,202500,1024,4096,3037500,159749820,598507920,
%U A185567 159749820,3037500,4096,16384,45562500,8977824540,126017211780,126017211780
%N A185567 T(n,k)=1/4 the number of nXk 0..3 arrays with no element equal both to the element above and to the element to its left.
%C A185567 Table starts
%C A185567 .....1.........4.............16..................64.....................256
%C A185567 .....4........60............900...............13500..................202500
%C A185567 ....16.......900..........50580.............2842560...............159749820
%C A185567 ....64.....13500........2842560...........598507920............126017211780
%C A185567 ...256....202500......159749820........126017211780..........99407416968000
%C A185567 ..1024...3037500.....8977824540......26533211918040.......78416544382742160
%C A185567 ..4096..45562500...504547256880....5586628402633500....61858104930689319360
%C A185567 .16384.683437500.28355191537860.1176277376648694960.48796145962555619907720
%H A185567 R. H. Hardin, <a href="/A185567/b185567.txt">Table of n, a(n) for n = 1..220</a>
%e A185567 Some solutions for 4X3 with a(1,1)=0
%e A185567 ..0..2..2....0..0..2....0..0..2....0..0..0....0..0..2....0..0..2....0..0..0
%e A185567 ..0..2..0....2..0..2....2..2..0....2..0..2....0..2..0....2..2..3....2..2..1
%e A185567 ..1..0..3....1..3..0....3..3..2....1..1..3....2..0..2....3..2..3....3..3..0
%e A185567 ..1..2..3....1..0..1....1..3..1....0..3..0....3..3..0....3..3..2....1..3..1
%Y A185567 Column 2 is 4*A001024(n-1)
%K A185567 nonn,tabl
%O A185567 1,2
%A A185567 _R. H. Hardin_ Jan 31 2011