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A235542 Number of (n+1)X(2+1) 0..1 arrays with the sum of each 2X2 subblock two median terms lexicographically nondecreasing rowwise and columnwise 1

%I

%S 48,222,1049,4348,17658,67012,247639,880814,3061429,10385988,34604232,

%T 113376954,366386257,1169544994,3694214596,11560700652,35884753502,

%U 110586677426,338628074707,1031035016352,3123343642588,9418695537368

%N Number of (n+1)X(2+1) 0..1 arrays with the sum of each 2X2 subblock two median terms lexicographically nondecreasing rowwise and columnwise

%C Column 2 of A235548

%H R. H. Hardin, <a href="/A235542/b235542.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 12*a(n-1) -48*a(n-2) +26*a(n-3) +319*a(n-4) -694*a(n-5) -524*a(n-6) +2932*a(n-7) -875*a(n-8) -5880*a(n-9) +4552*a(n-10) +6378*a(n-11) -7363*a(n-12) -3518*a(n-13) +6068*a(n-14) +520*a(n-15) -2576*a(n-16) +352*a(n-17) +448*a(n-18) -128*a(n-19)

%e Some solutions for n=5

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 12 2014

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Last modified October 23 04:06 EDT 2021. Contains 348211 sequences. (Running on oeis4.)