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%I #5 Mar 31 2012 12:36:45
%S 10,90,631,3567,16493,64018,213013,621757,1626046,3878550,8560638,
%T 17688966,34541082,64226182,114429139,196357695,325924563,525198174,
%U 824157734,1262790173,1893568514,2784353134,4021759333,5715036571
%N Number of nX2 0..4 arrays with rows and columns lexicographically nondecreasing and no element equal to the number of horizontal and vertical neighbors equal to itself
%C Column 2 of A201729
%H R. H. Hardin, <a href="/A201723/b201723.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (27/560)*n^8 + (153/140)*n^7 - (1841/40)*n^6 + (29593/40)*n^5 - (474291/80)*n^4 + (1992631/120)*n^3 + (7057023/70)*n^2 - (200552137/210)*n + 2321607 for n>13
%e Some solutions for n=6
%e ..0..2....0..0....2..4....0..0....0..0....0..3....0..0....2..3....0..2....0..0
%e ..0..4....0..3....2..4....0..2....1..4....0..3....0..0....3..4....0..2....0..1
%e ..2..4....2..0....3..2....1..3....2..2....0..3....0..4....4..0....0..3....0..2
%e ..3..0....2..0....4..1....2..1....3..1....0..3....1..0....4..0....0..3....1..0
%e ..3..0....3..4....4..4....3..2....3..3....0..3....4..0....4..0....2..0....2..0
%e ..3..1....4..2....4..4....3..2....4..3....0..3....4..4....4..1....2..0....2..4
%K nonn
%O 1,1
%A _R. H. Hardin_ Dec 04 2011
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