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Number of (n+3) X 6 binary arrays with consecutive windows of four bits considered as a binary number nondecreasing in every row and column.
1

%I #9 Jun 03 2018 07:57:24

%S 104976,153874,225858,330853,481798,695114,991196,1394929,1936228,

%T 2650602,3579742,4772133,6283690,8178418,10529096,13417985,16937560,

%U 21191266,26294298,32374405,39572718,48044602,57960532,69506993,82887404

%N Number of (n+3) X 6 binary arrays with consecutive windows of four bits considered as a binary number nondecreasing in every row and column.

%C Column 3 of A202939.

%H R. H. Hardin, <a href="/A202934/b202934.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (1/30)*n^6 + (16/5)*n^5 + (875/12)*n^4 + (2116/3)*n^3 + (103801/20)*n^2 + (407932/15)*n + 71809.

%F Conjectures from _Colin Barker_, Jun 03 2018: (Start)

%F G.f.: x*(104976 - 580958*x + 1353236*x^2 - 1692959*x^3 + 1197415*x^4 - 453495*x^5 + 71809*x^6) / (1 - x)^7.

%F a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>7.

%F (End)

%e Some solutions for n=2:

%e ..0..0..0..0..0..0....0..0..1..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0

%e ..0..0..0..0..1..1....0..0..1..0..1..0....0..0..1..1..0..0....0..0..0..1..0..1

%e ..0..1..1..1..1..1....0..0..1..1..1..1....0..0..1..1..0..1....0..0..1..0..1..0

%e ..0..0..1..0..1..0....0..0..1..1..1..1....0..0..1..0..0..1....0..0..1..0..0..0

%e ..0..0..1..0..1..1....0..0..1..1..1..0....0..0..0..0..1..0....0..0..0..1..1..0

%Y Cf. A202939.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 26 2011