%I #8 Sep 24 2018 02:48:02
%S 2,16,34,232,522,3768,8450,60824,136474,982552,2204498,15870936,
%T 35608874,256361112,575185186,4140964568,9290884794,66888415128,
%U 150074347890,1080439106264,2424129709770,17452180031640,39156624254530
%N Number of whitesquare subarrays of (n+2) X (3+2) 0..3 arrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.
%H R. H. Hardin, <a href="/A230937/b230937.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 16*a(n2) +3*a(n4) 10*a(n6) +24*a(n8) 16*a(n10).
%F Empirical g.f.: 2*x*(1 + 8*x + x^2  12*x^3  14*x^4 + 4*x^5 + 8*x^6) / (1  16*x^2  3*x^4 + 10*x^6  24*x^8 + 16*x^10).  _Colin Barker_, Sep 23 2018
%e Some solutions for n=4:
%e ..0..x..0..x..0....0..x..2..x..2....0..x..2..x..2....0..x..2..x..2
%e ..x..1..x..1..x....x..1..x..3..x....x..1..x..3..x....x..1..x..3..x
%e ..0..x..2..x..0....2..x..0..x..2....0..x..0..x..2....0..x..0..x..0
%e ..x..1..x..3..x....x..3..x..1..x....x..3..x..3..x....x..3..x..1..x
%e ..0..x..2..x..2....2..x..0..x..0....2..x..2..x..2....0..x..2..x..0
%e ..x..1..x..1..x....x..1..x..3..x....x..1..x..1..x....x..1..x..3..x
%Y Column 3 of A230940.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 01 2013
