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A235180 Number of (n+1)X(2+1) 0..5 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 5, with no adjacent elements equal (constant stress tilted 1X1 tilings) 1

%I

%S 212,560,1400,3796,9780,27080,71244,200164,535384,1520236,4122676,

%T 11802552,32387932,93334500,258770168,749813004,2097549460,6106147288,

%U 17214643468,50312715684,142794762392,418766264044,1195325876852

%N Number of (n+1)X(2+1) 0..5 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 5, with no adjacent elements equal (constant stress tilted 1X1 tilings)

%C Column 2 of A235186

%H R. H. Hardin, <a href="/A235180/b235180.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +29*a(n-2) -88*a(n-3) -327*a(n-4) +1003*a(n-5) +1816*a(n-6) -5577*a(n-7) -5295*a(n-8) +15566*a(n-9) +8705*a(n-10) -20575*a(n-11) -9813*a(n-12) +12552*a(n-13) +5962*a(n-14) -3436*a(n-15) -1676*a(n-16) +336*a(n-17) +168*a(n-18)

%e Some solutions for n=4

%e ..4..5..4....2..0..4....3..0..4....3..0..3....0..2..0....0..3..2....4..2..4

%e ..5..1..5....0..3..2....2..4..3....0..2..0....4..1..4....3..1..5....1..4..1

%e ..2..3..2....2..0..4....4..1..5....3..0..3....2..4..2....0..3..2....4..2..4

%e ..5..1..5....0..3..2....1..3..2....0..2..0....5..2..5....3..1..5....2..5..2

%e ..2..3..2....3..1..5....3..0..4....4..1..4....1..3..1....0..3..2....5..3..5

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 04 2014

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Last modified May 18 23:31 EDT 2022. Contains 353826 sequences. (Running on oeis4.)