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A223678 Number of nX6 0..1 arrays with rows and antidiagonals unimodal.

%I A223678 #6 Jul 23 2025 04:23:11
%S A223678 22,484,7745,105995,1363639,17068664,210660192,2577807779,31402790284,
%T A223678 381690187059,4633795630120,56218000664764,681802614308980,
%U A223678 8267243693472174,100235088136900011,1215221703756846658
%N A223678 Number of nX6 0..1 arrays with rows and antidiagonals unimodal.
%C A223678 Column 6 of A223680
%H A223678 R. H. Hardin, <a href="/A223678/b223678.txt">Table of n, a(n) for n = 1..210</a>
%F A223678 Empirical: a(n) = 22*a(n-1) -151*a(n-2) +461*a(n-3) -797*a(n-4) -4885*a(n-5) +28261*a(n-6) +53750*a(n-7) -398208*a(n-8) +360701*a(n-9) +952132*a(n-10) -5152120*a(n-11) +7572284*a(n-12) +6140578*a(n-13) -18089482*a(n-14) -653352*a(n-15) +28175814*a(n-16) +67786763*a(n-17) -392210630*a(n-18) +717516941*a(n-19) -875602031*a(n-20) +904784133*a(n-21) -930560603*a(n-22) +1037859554*a(n-23) -1035189626*a(n-24) +1256680629*a(n-25) -1842818297*a(n-26) +2256596552*a(n-27) -2217424297*a(n-28) +1613743557*a(n-29) -832569368*a(n-30) +412448612*a(n-31) -308789168*a(n-32) +241553248*a(n-33) -122269952*a(n-34) +31245376*a(n-35) -2822400*a(n-36)
%e A223678 Some solutions for n=3
%e A223678 ..0..1..1..1..1..0....1..0..0..0..0..0....0..0..1..1..1..1....0..0..0..1..0..0
%e A223678 ..0..1..1..0..0..0....0..0..0..0..1..1....0..0..0..0..0..1....0..1..1..0..0..0
%e A223678 ..1..0..0..0..0..0....0..0..0..0..1..1....0..0..0..0..1..0....0..1..1..1..1..0
%K A223678 nonn
%O A223678 1,1
%A A223678 _R. H. Hardin_ Mar 25 2013