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A202799 Number of nX5 binary arrays with every one adjacent to another one horizontally or vertically.

%I A202799 #7 Jul 22 2025 16:50:46
%S A202799 12,454,11988,311144,8222576,217145076,5730640104,151245101550,
%T A202799 3991784606164,105354316048660,2780593210008194,73387575404296206,
%U A202799 1936901875857360748,51120219046394982056,1349204535780755578282
%N A202799 Number of nX5 binary arrays with every one adjacent to another one horizontally or vertically.
%C A202799 Column 5 of A202802
%H A202799 R. H. Hardin, <a href="/A202799/b202799.txt">Table of n, a(n) for n = 1..210</a>
%F A202799 Empirical: a(n) = 27*a(n-1) -82*a(n-2) +1720*a(n-3) -876*a(n-4) +36142*a(n-5) +36267*a(n-6) +228084*a(n-7) +1329202*a(n-8) -3356034*a(n-9) -15601554*a(n-10) +6682402*a(n-11) +62222338*a(n-12) +8454105*a(n-13) -144765880*a(n-14) -62367040*a(n-15) +251331688*a(n-16) +212121408*a(n-17) -212078096*a(n-18) -315914880*a(n-19) -123060608*a(n-20) -12403456*a(n-21) +277981952*a(n-22) +391540736*a(n-23) +190742528*a(n-24) +156106752*a(n-25) +22544384*a(n-26) +16777216*a(n-27)
%e A202799 Some solutions for n=3
%e A202799 ..1..1..1..0..0....0..0..1..1..1....1..1..1..1..1....1..1..0..0..1
%e A202799 ..0..0..0..0..1....0..1..1..1..0....0..1..0..1..1....1..0..1..0..1
%e A202799 ..1..1..1..1..1....0..0..1..1..1....1..1..1..0..1....1..1..1..0..0
%K A202799 nonn
%O A202799 1,1
%A A202799 _R. H. Hardin_ Dec 24 2011