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A206985 Number of nX6 0..1 arrays avoiding the patterns 0 1 0 or 1 0 1 in any row, column, diagonal or antidiagonal.

%I A206985 #7 Jul 22 2025 19:53:27
%S A206985 26,676,1066,5804,27762,119224,539576,2511348,11347860,51289536,
%T A206985 234531890,1067836614,4847382862,22063872636,100447611768,
%U A206985 456793739872,2077973014524,9455702551722,43017605222256,195696521320564
%N A206985 Number of nX6 0..1 arrays avoiding the patterns 0 1 0 or 1 0 1 in any row, column, diagonal or antidiagonal.
%C A206985 Column 6 of A206987
%H A206985 R. H. Hardin, <a href="/A206985/b206985.txt">Table of n, a(n) for n = 1..210</a>
%F A206985 Empirical: a(n) = 9*a(n-1) -32*a(n-2) +93*a(n-3) -259*a(n-4) +478*a(n-5) -534*a(n-6) -93*a(n-7) +36*a(n-8) +1556*a(n-9) +294*a(n-10) -3651*a(n-11) +8447*a(n-12) -690*a(n-13) -5674*a(n-14) +6636*a(n-15) +51944*a(n-16) -50911*a(n-17) -34119*a(n-18) -76215*a(n-19) +126430*a(n-20) +211178*a(n-21) +3381*a(n-22) -301486*a(n-23) -330384*a(n-24) +322877*a(n-25) +298439*a(n-26) -95421*a(n-27) -522981*a(n-28) -40984*a(n-29) +78447*a(n-30) +421368*a(n-31) +154765*a(n-32) -197659*a(n-33) -37604*a(n-34) -116015*a(n-35) +191027*a(n-36) +83557*a(n-37) +958*a(n-38) -67177*a(n-39) -70907*a(n-40) -22943*a(n-41) +12080*a(n-42) +7672*a(n-43) +10360*a(n-44) -1803*a(n-45) +294*a(n-46) -875*a(n-47) +109*a(n-48) -48*a(n-49) +4*a(n-50) for n>53
%e A206985 Some solutions for n=4
%e A206985 ..0..1..1..0..0..1....1..1..1..0..0..1....1..0..0..1..1..1....0..1..1..0..0..0
%e A206985 ..0..1..1..0..0..1....0..1..1..0..0..1....0..0..0..0..0..0....1..1..1..1..1..1
%e A206985 ..1..1..1..0..0..0....0..1..1..0..0..0....0..0..0..0..0..0....1..1..1..1..1..1
%e A206985 ..1..1..1..0..0..0....1..1..1..0..0..0....0..1..1..0..0..1....1..1..1..0..0..0
%K A206985 nonn
%O A206985 1,1
%A A206985 _R. H. Hardin_ Feb 14 2012