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%I #7 Jun 18 2022 23:07:52
%S 392,1120,2744,8392,22568,71896,206360,675064,2026472,6751000,
%T 20907224,70560952,223435688,761260696,2450452760,8407382584,
%U 27402409832,94504374040,311023311704,1076774857912,3571073152808,12398475609496
%N Number of (n+1) X (2+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 7 (constant-stress 1 X 1 tilings).
%C Column 2 of A235319.
%H R. H. Hardin, <a href="/A235313/b235313.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) +47*a(n-2) -200*a(n-3) -901*a(n-4) +4204*a(n-5) +8957*a(n-6) -48440*a(n-7) -47194*a(n-8) +334096*a(n-9) +101948*a(n-10) -1410080*a(n-11) +170136*a(n-12) +3549696*a(n-13) -1446912*a(n-14) -4861440*a(n-15) +2954880*a(n-16) +2764800*a(n-17) -2073600*a(n-18).
%e Some solutions for n=4:
%e 5 1 5 4 0 3 4 0 4 5 0 4 2 6 0 0 4 0 5 1 5
%e 2 5 2 1 4 0 2 5 2 1 3 0 5 2 3 5 2 5 0 3 0
%e 5 1 5 6 2 5 4 0 4 6 1 5 2 6 0 0 4 0 4 0 4
%e 0 3 0 2 5 1 0 3 0 2 4 1 6 3 4 5 2 5 1 4 1
%e 5 1 5 6 2 5 6 2 6 5 0 4 2 6 0 1 5 1 5 1 5
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2014