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A203974 Number of nX7 0..2 arrays with every 1 immediately preceded by 0 to the left or above, and every 2 immediately preceded by 0 1 to the left or above.

%I A203974 #7 Jul 22 2025 17:42:01
%S A203974 44,5569,1107082,180623180,30104480870,5061444598545,847220834970347,
%T A203974 141937054743243405,23779975312437117115,3983658769957290205062,
%U A203974 667379066179974381638813,111804522576410924713391638
%N A203974 Number of nX7 0..2 arrays with every 1 immediately preceded by 0 to the left or above, and every 2 immediately preceded by 0 1 to the left or above.
%C A203974 Column 7 of A203975
%H A203974 R. H. Hardin, <a href="/A203974/b203974.txt">Table of n, a(n) for n = 1..210</a>
%e A203974 Some solutions for n=2
%e A203974 ..0..1..0..0..0..1..0....0..0..0..1..0..0..0....0..1..0..1..2..0..0
%e A203974 ..0..1..2..1..1..0..1....0..0..0..0..1..2..0....0..1..2..0..0..1..0
%K A203974 nonn
%O A203974 1,1
%A A203974 _R. H. Hardin_ Jan 08 2012