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A235016 Number of (n+1) X (7+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings). 1

%I

%S 11400,14600,19560,28968,44680,74888,128776,235240,437928,853928,

%T 1698888,3513672,7432648,16248488,36317416,83329384,194803464,

%U 464181896,1121480328,2744583528,6780016936,16886392616,42310371784,106547257288

%N Number of (n+1) X (7+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).

%H R. H. Hardin, <a href="/A235016/b235016.txt">Table of n, a(n) for n = 1..209</a>

%F Empirical: a(n) = 5*a(n-1) + a(n-2) - 38*a(n-3) + 33*a(n-4) + 97*a(n-5) - 127*a(n-6) - 88*a(n-7) + 154*a(n-8) + 12*a(n-9) - 48*a(n-10).

%F Empirical g.f.: 8*x*(1425 - 5300*x - 8105*x^2 + 43721*x^3 + 7360*x^4 - 127725*x^5 + 24570*x^6 + 152306*x^7 - 36540*x^8 - 58464*x^9) / ((1 - x)*(1 - 2*x)*(1 - x - x^2)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - x - 4*x^2)). - _Colin Barker_, Oct 17 2018

%e Some solutions for n=4:

%e 4 0 2 0 1 2 1 0 3 2 3 2 3 2 0 2 0 4 2 4 0 4 2 3

%e 3 2 1 2 0 4 0 2 1 3 1 3 1 3 4 3 2 3 4 3 2 3 4 2

%e 4 0 2 0 1 2 1 0 3 2 3 2 3 2 0 2 4 2 0 2 4 2 0 1

%e 3 2 1 2 0 4 0 2 1 3 1 3 1 3 4 3 2 3 4 3 2 3 4 2

%e 4 0 2 0 1 2 1 0 3 2 3 2 3 2 0 2 4 2 0 2 4 2 0 1

%Y Column 7 of A235017.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 02 2014

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Last modified August 10 16:24 EDT 2022. Contains 356039 sequences. (Running on oeis4.)