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A207805 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

%I A207805 #7 Jul 22 2025 20:51:22
%S A207805 16,256,1260,9040,57184,379444,2472540,16206848,106011620,694009184,
%T A207805 4542097536,29729773868,194584835796,1273595422280,8335887348348,
%U A207805 54559852092224,357103742801920,2337306999308120,15298084063769760
%N A207805 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 0 and 1 0 1 vertically.
%C A207805 Column 5 of A207808
%H A207805 R. H. Hardin, <a href="/A207805/b207805.txt">Table of n, a(n) for n = 1..210</a>
%F A207805 Empirical: a(n) = 5*a(n-1) +4*a(n-2) +a(n-3) +156*a(n-4) +450*a(n-5) +1534*a(n-6) +284*a(n-7) -6636*a(n-8) -20429*a(n-9) -58954*a(n-10) -85923*a(n-11) -30935*a(n-12) +298240*a(n-13) +715086*a(n-14) +668992*a(n-15) -111819*a(n-16) -1321603*a(n-17) -1450152*a(n-18) -1115039*a(n-19) +135434*a(n-20) +394522*a(n-21) +1112524*a(n-22) +852540*a(n-23) +503094*a(n-24) -120123*a(n-25) -590386*a(n-26) -94045*a(n-27) -172107*a(n-28) +175024*a(n-29) -88826*a(n-30) -2748*a(n-31) +28009*a(n-32) -5237*a(n-33) +22780*a(n-34) -15137*a(n-35) +3224*a(n-36) +3094*a(n-37) -2442*a(n-38) +500*a(n-39) +40*a(n-40) -87*a(n-41) +10*a(n-42) -a(n-43) -a(n-44)
%e A207805 Some solutions for n=4
%e A207805 ..1..1..0..1..1....0..1..1..0..0....1..0..1..1..1....1..0..1..1..1
%e A207805 ..1..1..0..1..0....0..1..1..0..1....0..1..1..1..1....0..1..0..1..1
%e A207805 ..1..0..1..0..0....1..0..1..1..1....0..1..1..1..1....0..1..0..1..1
%e A207805 ..1..0..1..0..1....1..0..1..1..0....1..1..0..1..1....0..1..1..0..1
%K A207805 nonn
%O A207805 1,1
%A A207805 _R. H. Hardin_ Feb 20 2012