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A186875 Number of (n+2) X 5 0..3 arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock. 1

%I

%S 19236,1201,6712,20152,28984,32992,37576,46624,73744,138808,251563,

%T 430558,737137,1213933,1970809,3305629,5489365,9050326,15264856,

%U 25456522,42050491,70609627,117651379,194582923,326053558,543547039,900491803

%N Number of (n+2) X 5 0..3 arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock.

%C Column 3 of A186881.

%H R. H. Hardin, <a href="/A186875/b186875.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 2*a(n-1) - a(n-2) + 3*a(n-3) - 6*a(n-4) + 3*a(n-5) + 3*a(n-6) - 3*a(n-7) for n>11.

%F Empirical g.f.: x*(19236 - 37271*x + 23546*x^2 - 49779*x^3 + 107205*x^4 - 75462*x^5 - 80919*x^6 + 72393*x^7 + 16011*x^8 - 4104*x^9 + 7803*x^10) / ((1 - x)*(1 - x - 3*x^3 + 3*x^4 - 3*x^6)). - _Colin Barker_, Apr 19 2018

%e Some solutions for 4 X 5:

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

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

%e ..0..1..0..0..1....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0

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

%Y Cf. A186881.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 28 2011

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Last modified October 21 22:47 EDT 2019. Contains 328315 sequences. (Running on oeis4.)