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%I #6 Jun 20 2022 20:29:51
%S 136,766,766,4296,4970,4296,24158,32070,32070,24158,135752,208412,
%T 236876,208412,135752,764190,1353986,1773484,1773484,1353986,764190,
%U 4299592,8846884,13227132,15427948,13227132,8846884,4299592,24233182,57811490
%N T(n,k) is the number of (n+1) X (k+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2 (constant-stress 1 X 1 tilings).
%C Table starts
%C 136 766 4296 24158 135752 764190
%C 766 4970 32070 208412 1353986 8846884
%C 4296 32070 236876 1773484 13227132 99877680
%C 24158 208412 1773484 15427948 133660366 1183467658
%C 135752 1353986 13227132 133660366 1337127500 13865878254
%C 764190 8846884 99877680 1183467658 13865878254 171702282736
%C 4299592 57811490 751361300 10438586426 142146253428 2098023535022
%C 24233182 380032300 5729616704 94449496104 1522643238010 27538386579098
%C 136504392 2498158614 43493374260 849993735464 16046511409532 353610525268640
%H R. H. Hardin, <a href="/A234169/b234169.txt">Table of n, a(n) for n = 1..112</a>
%F Empirical for column k:
%F k=1: a(n) = 4*a(n-1) +41*a(n-2) -132*a(n-3) -264*a(n-4).
%F k=2: [order 17].
%F k=3: [order 80].
%e Some solutions for n=2, k=4:
%e 1 4 1 2 3 1 1 0 1 3 1 3 4 3 0 0 1 3 0 3
%e 2 3 2 1 0 1 3 0 3 3 3 3 2 3 2 3 2 2 1 2
%e 4 3 0 1 2 4 4 3 4 2 1 3 4 3 4 3 4 2 3 2
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_, Dec 20 2013
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