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%I #10 Nov 16 2021 21:39:51
%S 13,169,1393,10621,75221,518001,3500117,23428181,155913829,1034324253,
%T 6848794157,45301138173,299456026377,1978795266229,13073066599357,
%U 86357724891721,570419071704225,3767635749133789,24884750059577649
%N Number of n X 4 0..1 arrays avoiding 0 0 0 horizontally and 0 0 1 vertically.
%C Column 4 of A207088.
%H R. H. Hardin, <a href="/A207084/b207084.txt">Table of n, a(n) for n = 1..210</a>
%H Robert Israel, <a href="/A207084/a207084.pdf">Maple-assisted proof of formula</a>
%F Empirical: a(n) = 11*a(n-1) -11*a(n-2) -195*a(n-3) +361*a(n-4) +1387*a(n-5) -2443*a(n-6) -5105*a(n-7) +6602*a(n-8) +9836*a(n-9) -7666*a(n-10) -9322*a(n-11) +3553*a(n-12) +4167*a(n-13) -507*a(n-14) -741*a(n-15) +25*a(n-16) +51*a(n-17) -a(n-18) -a(n-19).
%F Formula confirmed by _Robert Israel_, May 15 2018 (see link).
%e Some solutions for n=4
%e ..1..1..0..1....1..1..0..1....1..0..0..1....0..0..1..1....1..1..0..1
%e ..0..1..0..1....1..0..0..1....0..1..1..0....1..1..1..1....1..1..0..1
%e ..1..0..0..1....0..1..0..0....1..0..1..0....0..1..1..1....0..1..0..0
%e ..0..1..0..1....1..1..0..1....1..1..1..0....0..1..1..0....0..1..0..0
%Y Cf. A207088.
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 15 2012
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