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%I #4 Mar 25 2018 11:28:14
%S 21,22,46,89,223,696,2335,8380,31001,116558,442314,1686894,6453062,
%T 24725894,94832665,363935417,1397133323,5364622673,20601302508,
%U 79119265773,303870780015,1167097983033,4482628695760,17217197273712
%N Number of nX7 0..1 arrays with every element equal to 0, 1 or 4 horizontally or vertically adjacent elements, with upper left element zero.
%C Column 7 of A301662.
%H R. H. Hardin, <a href="/A301661/b301661.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) -5*a(n-2) +14*a(n-3) -44*a(n-4) -2*a(n-5) -63*a(n-6) +117*a(n-7) +133*a(n-8) +386*a(n-9) +126*a(n-10) -575*a(n-11) -1064*a(n-12) -876*a(n-13) +203*a(n-14) +1305*a(n-15) +1617*a(n-16) +681*a(n-17) -882*a(n-18) -1502*a(n-19) -879*a(n-20) +297*a(n-21) +793*a(n-22) +486*a(n-23) +6*a(n-24) -191*a(n-25) -108*a(n-26) -14*a(n-27) +20*a(n-28) +12*a(n-29) +4*a(n-30) +a(n-31)
%e Some solutions for n=5
%e ..0..1..0..1..0..1..0. .0..1..0..1..0..1..1. .0..1..0..0..1..0..1
%e ..1..0..1..0..0..0..1. .1..0..1..1..1..0..0. .1..0..1..1..0..1..0
%e ..0..0..0..1..0..1..0. .0..1..0..1..0..1..1. .0..1..0..0..1..1..1
%e ..1..0..1..0..1..0..1. .1..1..1..0..1..0..0. .1..0..1..1..0..1..0
%e ..0..1..0..1..0..1..0. .0..1..0..1..0..1..1. .0..1..0..0..1..0..1
%Y Cf. A301662.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 25 2018
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