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%I #4 Dec 17 2017 15:08:28
%S 4,28,132,671,3444,17558,89613,457188,2333009,11905494,60751194,
%T 310004765,1581914211,8072288131,41191772847,210195946958,
%U 1072600980393,5473335132061,27929675517731,142521288635027,727266512789731
%N Number of nX3 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 1, 2 or 4 neighboring 1s.
%C Column 3 of A296643.
%H R. H. Hardin, <a href="/A296638/b296638.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) -a(n-2) +11*a(n-3) -18*a(n-4) +13*a(n-5) -36*a(n-6) +63*a(n-7) -23*a(n-8) -95*a(n-9) -52*a(n-10) +62*a(n-11) -14*a(n-12) -78*a(n-13) +14*a(n-14) +51*a(n-15) +59*a(n-16) +80*a(n-17) +33*a(n-18) -30*a(n-19) -32*a(n-20) -10*a(n-21) -a(n-22)
%e Some solutions for n=7
%e ..0..0..0. .0..1..0. .0..0..1. .0..0..0. .1..1..0. .0..0..0. .0..1..1
%e ..1..1..1. .0..1..0. .0..1..0. .1..0..1. .0..1..0. .0..1..1. .1..0..0
%e ..0..0..1. .0..1..1. .0..0..0. .1..0..1. .0..1..0. .0..1..0. .0..1..0
%e ..1..1..0. .0..0..1. .1..1..0. .1..1..0. .0..0..1. .1..1..0. .1..1..1
%e ..0..0..0. .0..0..0. .1..0..1. .0..0..0. .1..1..1. .0..0..0. .0..1..0
%e ..1..1..1. .0..0..1. .0..0..1. .0..1..0. .1..0..0. .1..0..0. .1..1..0
%e ..0..0..1. .0..1..0. .0..1..0. .0..1..0. .0..0..0. .1..1..0. .0..0..0
%Y Cf. A296643.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 17 2017
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