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Number of nX7 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 0 1 vertically
1

%I #5 Mar 31 2012 12:37:19

%S 28,784,2654,11509,59252,235872,887114,3488718,13324700,49528948,

%T 184808314,687726602,2538842648,9356257550,34457742152,126613738962,

%U 464595415916,1703705288482,6242056357676,22851249560906,83609513888316

%N Number of nX7 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 0 1 vertically

%C Column 7 of A207762

%H R. H. Hardin, <a href="/A207761/b207761.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 9*a(n-1) -30*a(n-2) +101*a(n-3) -452*a(n-4) +1080*a(n-5) -2212*a(n-6) +7988*a(n-7) -14310*a(n-8) +18574*a(n-9) -74548*a(n-10) +97674*a(n-11) -59812*a(n-12) +477460*a(n-13) -408258*a(n-14) -76060*a(n-15) -2426098*a(n-16) +1052702*a(n-17) +1527766*a(n-18) +9776968*a(n-19) -978888*a(n-20) -7207648*a(n-21) -30286394*a(n-22) -3635038*a(n-23) +19889764*a(n-24) +70635534*a(n-25) +17114220*a(n-26) -37149004*a(n-27) -121787501*a(n-28) -35300157*a(n-29) +49526360*a(n-30) +154324589*a(n-31) +41825606*a(n-32) -49157144*a(n-33) -142598668*a(n-34) -27479092*a(n-35) +38216016*a(n-36) +96382504*a(n-37) +4500656*a(n-38) -23708240*a(n-39) -48440992*a(n-40) +7538688*a(n-41) +11797440*a(n-42) +18533248*a(n-43) -7068544*a(n-44) -3979392*a(n-45) -5485568*a(n-46) +3083776*a(n-47) +727552*a(n-48) +1075712*a(n-49) -813056*a(n-50) -5120*a(n-51) -122880*a(n-52) +161792*a(n-53) -20480*a(n-54) +8192*a(n-55) -16384*a(n-56) for n>60

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 19 2012