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A235180
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Number of (n+1) X (2+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).
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1
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212, 560, 1400, 3796, 9780, 27080, 71244, 200164, 535384, 1520236, 4122676, 11802552, 32387932, 93334500, 258770168, 749813004, 2097549460, 6106147288, 17214643468, 50312715684, 142794762392, 418766264044, 1195325876852
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OFFSET
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1,1
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LINKS
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FORMULA
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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).
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EXAMPLE
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Some solutions for n=4:
4 5 4 2 0 4 3 0 4 3 0 3 0 2 0 0 3 2 4 2 4
5 1 5 0 3 2 2 4 3 0 2 0 4 1 4 3 1 5 1 4 1
2 3 2 2 0 4 4 1 5 3 0 3 2 4 2 0 3 2 4 2 4
5 1 5 0 3 2 1 3 2 0 2 0 5 2 5 3 1 5 2 5 2
2 3 2 3 1 5 3 0 4 4 1 4 1 3 1 0 3 2 5 3 5
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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