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%I #8 Jun 03 2018 08:01:33
%S 1,9,63,323,1629,8534,44885,234728,1226239,6410598,33519355,175245104,
%T 916179060,4789827101,25041566175,130918895222,684451568104,
%U 3578352893257,18707840821315,97805696796991,511333945789384
%N Number of n X 2 0..2 arrays with every nonzero element less than or equal to some NW, E or S neighbor.
%C Column 2 of A202988.
%H R. H. Hardin, <a href="/A202982/b202982.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 9*a(n-1) -28*a(n-2) +60*a(n-3) -102*a(n-4) +84*a(n-5) -44*a(n-6) +25*a(n-7).
%F Empirical g.f.: x*(1 + 10*x^2 - 52*x^3 + 48*x^4 - 29*x^5 + 25*x^6) / (1 - 9*x + 28*x^2 - 60*x^3 + 102*x^4 - 84*x^5 + 44*x^6 - 25*x^7). - _Colin Barker_, Jun 03 2018
%e Some solutions for n=5:
%e ..1..1....1..0....2..0....0..0....2..0....1..0....0..1....0..1....0..1....1..0
%e ..1..1....1..1....2..0....0..2....2..2....2..1....2..1....2..2....2..1....1..2
%e ..1..1....0..0....2..0....2..2....1..1....2..1....2..2....1..2....2..2....2..2
%e ..2..0....1..1....2..2....2..2....2..1....2..0....1..1....1..1....2..1....0..2
%e ..2..2....0..1....1..1....1..1....2..2....2..2....0..0....1..1....2..2....0..0
%Y Cf. A202988.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 26 2011