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 A235285 Number of (n+1)X(4+1) 0..3 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant stress 1X1 tilings) 1

%I

%S 136,188,248,380,544,908,1400,2492,4096,7628,13208,25340,45664,89228,

%T 165560,326972,619456,1230668,2366168,4715900,9162784,18292748,

%U 35811320,71557052,140857216,281583308,556527128,1112792060,2205927904,4411331468

%N Number of (n+1)X(4+1) 0..3 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant stress 1X1 tilings)

%C Column 4 of A235289

%H R. H. Hardin, <a href="/A235285/b235285.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +3*a(n-2) -15*a(n-3) +4*a(n-4) +18*a(n-5) -12*a(n-6)

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 05 2014

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Last modified December 7 12:17 EST 2021. Contains 349581 sequences. (Running on oeis4.)