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Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock diagonal maximum plus antidiagonal median nondecreasing horizontally and vertically
2

%I #4 Jan 13 2015 21:22:27

%S 512,2908,14096,66144,299472,1303600,5525648,23034276,94841688,

%T 386810592,1566259600,6306887152,25284981392,101016575076,

%U 402445751816,1599719168672,6347297006736,25147307796592,99511016673904

%N Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock diagonal maximum plus antidiagonal median nondecreasing horizontally and vertically

%C Column 1 of A253801

%H R. H. Hardin, <a href="/A253794/b253794.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 8*a(n-1) -19*a(n-2) +13*a(n-3) -8*a(n-4) +27*a(n-5) -79*a(n-6) +156*a(n-7) -217*a(n-8) -235*a(n-9) +964*a(n-10) -1201*a(n-11) +1488*a(n-12) -256*a(n-13) -1064*a(n-14) +994*a(n-15) -1048*a(n-16) +254*a(n-17) -132*a(n-18) +400*a(n-19) -204*a(n-20) -56*a(n-21) +256*a(n-22) -40*a(n-23) +16*a(n-24) -16*a(n-26)

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 13 2015