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A206005 Number of (n+1)X4 0..2 arrays with the number of clockwise edge increases in every 2X2 subblock equal to one, and every 2X2 determinant nonzero 1

%I

%S 228,980,2728,12068,33572,150396,419108,1895206,5286788,24077032,

%T 67200552,307662788,858930264,3947689488,11022344624,50802408116,

%U 141850386688,655129480632,1829250701552,8460734276112,23623691166880

%N Number of (n+1)X4 0..2 arrays with the number of clockwise edge increases in every 2X2 subblock equal to one, and every 2X2 determinant nonzero

%C Column 3 of A206010

%H R. H. Hardin, <a href="/A206005/b206005.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 32*a(n-2) -356*a(n-4) +1590*a(n-6) -2264*a(n-8) -8*a(n-10) +1168*a(n-12) -336*a(n-14) for n>18

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 02 2012

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Last modified October 16 00:29 EDT 2021. Contains 348034 sequences. (Running on oeis4.)