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%I #6 Jun 20 2022 19:51:36
%S 1148,4416,16580,69336,281612,1253088,5385236,25119456,112545548,
%T 544181136,2514628340,12495760896,59077785452,299739293328,
%U 1441310414996,7429688790336,36177693563468,188779231755216,927888726542900
%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 5 (constant-stress 1 X 1 tilings).
%H R. H. Hardin, <a href="/A234684/b234684.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) +136*a(n-2) -1036*a(n-3) -7837*a(n-4) +67291*a(n-5) +245614*a(n-6) -2526790*a(n-7) -4355332*a(n-8) +60808804*a(n-9) +36086728*a(n-10) -982312744*a(n-11) +135510432*a(n-12) +10839179904*a(n-13) -6945594624*a(n-14) -81450996480*a(n-15) +81465827328*a(n-16) +407151166464*a(n-17) -514409232384*a(n-18) -1284949370880*a(n-19) +1874710241280*a(n-20) +2296420761600*a(n-21) -3685898649600*a(n-22) -1755758592000*a(n-23) +3009871872000*a(n-24).
%e Some solutions for n=4:
%e 1 1 2 5 1 0 1 5 2 4 4 4 6 6 6 5 1 5 0 4 4
%e 5 0 6 0 1 5 5 4 6 6 1 6 6 1 6 5 6 5 6 5 0
%e 2 2 3 0 6 5 0 4 1 2 2 2 3 3 3 0 6 0 6 0 0
%e 1 6 2 5 6 0 2 1 3 0 5 0 5 0 5 0 1 0 1 0 5
%e 2 2 3 0 6 5 1 5 2 6 6 6 5 5 5 5 1 5 1 5 5
%Y Column 2 of A234690.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 29 2013
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