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%I #4 Sep 22 2013 21:54:43
%S 30,282,2187,13345,66503,281016,1037193,3420692,10260128,28379127,
%T 73192023,177601008,408454945,895812869,1883191437,3811219431,
%U 7453126082,14128822736,26035706883,46749593643,81969420795,140605855270
%N Number of nX7 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, rows lexicographically nondecreasing, and columns lexicographically nonincreasing
%C Column 7 of A229428
%H R. H. Hardin, <a href="/A229427/b229427.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (1/660441600)*n^14 + (1/9434880)*n^13 + (1/311850)*n^12 + (283/4989600)*n^11 + (23/34560)*n^10 + (5/896)*n^9 + (55843/1587600)*n^8 + (154153/907200)*n^7 + (4503127/7257600)*n^6 + (1244953/725760)*n^5 + (56059/14400)*n^4 + (1646347/302400)*n^3 + (401116003/50450400)*n^2 + (124079/24024)*n + 5
%e Some solutions for n=4
%e ..1..1..0..0..0..0..0....1..1..1..1..0..0..0....1..1..0..0..0..0..0
%e ..1..1..0..0..0..0..0....2..1..1..1..0..0..0....1..1..1..1..0..0..0
%e ..1..1..0..0..0..0..0....2..2..2..1..1..0..0....2..2..1..1..1..1..1
%e ..1..1..0..0..0..0..0....2..2..2..1..1..0..0....2..2..2..2..2..2..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Sep 22 2013
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