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A206312 Number of (n+1)X3 0..3 arrays with the number of clockwise edge increases in every 2X2 subblock equal to two, and every 2X2 determinant nonzero 1

%I

%S 873,14990,258452,4466450,77132181,1332632711,23019152735,

%T 397663246671,6869398174303,118667836512792,2049943888882611,

%U 35412251178185627,611735705434058145,10567560415916348461,182551476583398721925

%N Number of (n+1)X3 0..3 arrays with the number of clockwise edge increases in every 2X2 subblock equal to two, and every 2X2 determinant nonzero

%C Column 2 of A206318

%H R. H. Hardin, <a href="/A206312/b206312.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-1) +178*a(n-2) +165*a(n-3) -2824*a(n-4) -4379*a(n-5) +21326*a(n-6) +27124*a(n-7) -88175*a(n-8) -686*a(n-9) +173432*a(n-10) -238738*a(n-11) -152649*a(n-12) +854730*a(n-13) -1223471*a(n-14) +1084153*a(n-15) -644627*a(n-16) +130265*a(n-17) +200912*a(n-18) -253639*a(n-19) +210358*a(n-20) -155058*a(n-21) +94508*a(n-22) -47283*a(n-23) +17559*a(n-24) -3954*a(n-25) -565*a(n-26) +581*a(n-27) -71*a(n-28) +6*a(n-29)

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 06 2012

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Last modified December 8 08:56 EST 2021. Contains 349594 sequences. (Running on oeis4.)