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A205761 Number of (n+1)X2 0..3 arrays with every 2X2 subblock having nonzero determinant and having the same number of clockwise edge increases as its horizontal and vertical neighbors 1

%I

%S 192,1262,8659,62607,462040,3490700,26672819,205747848,1595214033,

%T 12413756669,96806542939,756001274858,5908892541394,46209002829411,

%U 361485247026700,2828432016655919,22133840165287141,173221954994087709

%N Number of (n+1)X2 0..3 arrays with every 2X2 subblock having nonzero determinant and having the same number of clockwise edge increases as its horizontal and vertical neighbors

%C Column 1 of A205768

%H R. H. Hardin, <a href="/A205761/b205761.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) +34*a(n-2) -95*a(n-3) -439*a(n-4) -247*a(n-5) +510*a(n-6) -285*a(n-7) -1600*a(n-8) +110*a(n-9) +1431*a(n-10) -111*a(n-11) -883*a(n-12) -96*a(n-13) +262*a(n-14) +100*a(n-15) +8*a(n-16) for n>17

%e Some solutions for 5X5

%e ..0..1....2..2....0..1....3..1....0..3....2..1....1..2....2..0....0..3....0..1

%e ..3..1....0..2....3..3....3..3....1..1....1..3....1..3....1..1....2..3....1..2

%e ..1..3....1..1....1..0....1..2....1..2....2..0....3..0....3..2....3..3....0..2

%e ..2..1....2..3....2..1....1..1....1..1....3..1....1..2....2..1....0..2....2..1

%e ..1..2....2..2....3..2....0..1....0..1....0..2....0..1....3..2....1..1....0..3

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 30 2012

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Last modified May 30 15:21 EDT 2020. Contains 334726 sequences. (Running on oeis4.)