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%I #9 Jun 19 2018 12:35:36
%S 62,95,110,190,218,374,434,742,866,1478,1730,2954,3458,5906,6914,
%T 11810,13826,23618,27650,47234,55298,94466,110594,188930,221186,
%U 377858,442370,755714,884738,1511426,1769474,3022850,3538946,6045698,7077890,12091394
%N Number of (n+1) X 5 0..2 arrays with every 2 X 2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.
%C Column 4 of A207149.
%H R. H. Hardin, <a href="/A207145/b207145.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 2*a(n-2) - 2*a(n-3) for n>11.
%F Empirical g.f.: x*(62 + 33*x - 109*x^2 + 14*x^3 - 2*x^4 - 4*x^5 + 4*x^6 - 4*x^7 + 4*x^8 - 4*x^9 + 4*x^10) / ((1 - x)*(1 - 2*x^2)). - _Colin Barker_, Jun 19 2018
%e Some solutions for n=4:
%e ..2..1..0..2..0....2..2..0..1..0....2..1..1..0..2....0..1..0..1..0
%e ..1..0..1..0..2....1..0..2..0..1....1..1..0..1..0....1..0..1..0..1
%e ..0..1..0..1..0....0..1..0..2..0....1..0..1..0..1....0..1..0..1..0
%e ..2..0..1..0..1....1..0..1..0..2....0..1..0..1..0....1..0..1..0..1
%e ..0..2..0..1..1....0..1..0..1..1....1..0..1..0..1....0..1..0..1..2
%Y Cf. A207149.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 15 2012
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