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%I #4 Mar 25 2013 11:13:32
%S 64,4096,83737,744272,4106403,17068664,58944337,178002044,484800960,
%T 1215412314,2845433373,6286999243,13216899344,26605753969,51547601046,
%U 96528061541,175319673499,309757515173,533729732564,898819275234
%N Number of 6Xn 0..1 arrays with rows and antidiagonals unimodal
%C Row 6 of A223680
%H R. H. Hardin, <a href="/A223684/b223684.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (271/5443200)*n^12 + (2327/3326400)*n^11 + (44081/1360800)*n^10 + (67031/362880)*n^9 + (1007557/226800)*n^8 + (1582/675)*n^7 + (211210703/1360800)*n^6 - (60265871/120960)*n^5 + (11265884461/5443200)*n^4 - (118533836/14175)*n^3 + (2826245099/151200)*n^2 - (113088191/3960)*n + 23503 for n>3
%e Some solutions for n=3
%e ..1..1..0....1..0..0....0..0..1....1..0..0....1..1..0....0..0..1....1..1..1
%e ..0..1..1....0..1..0....1..0..0....1..1..1....0..0..1....0..1..0....0..1..1
%e ..1..1..0....0..1..1....0..1..1....1..1..1....0..1..0....1..1..1....1..1..1
%e ..0..0..1....1..1..0....1..0..0....0..0..0....0..0..1....0..1..1....0..1..1
%e ..0..1..1....1..1..0....0..1..1....0..1..0....0..1..0....0..0..0....0..1..1
%e ..0..1..1....1..1..0....1..0..0....1..1..0....0..0..0....0..1..0....0..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 25 2013