%I #8 Jun 20 2022 19:21:46
%S 47306,127586,334938,1108418,3530906,13445762,48741018,204403250,
%T 809806586,3649630466,15448766778,73732987538,328732631066,
%U 1644074979362,7638831660378,39686386752050,190506531532346,1020461790949826
%N Number of (n+1) X (4+1) 0..7 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 6 (constant-stress 1 X 1 tilings).
%H R. H. Hardin, <a href="/A234708/b234708.txt">Table of n, a(n) for n = 1..77</a>
%F Empirical: a(n) = 13*a(n-1) +163*a(n-2) -2779*a(n-3) -9420*a(n-4) +268200*a(n-5) +60770*a(n-6) -15439130*a(n-7) +22995763*a(n-8) +589369361*a(n-9) -1588530069*a(n-10) -15656100243*a(n-11) +58787313370*a(n-12) +294085396250*a(n-13) -1450484076640*a(n-14) -3845621898440*a(n-15) +25550700910752*a(n-16) +32289252593664*a(n-17) -330371143423376*a(n-18) -113428722066352*a(n-19) +3163397610252320*a(n-20) -1019517140684000*a(n-21) -22338341568842880*a(n-22) +18872130722296320*a(n-23) +114348342295028736*a(n-24) -148610586143628288*a(n-25) -409381709070163968*a(n-26) +722386331480346624*a(n-27) +952125730341396480*a(n-28) -2277950012653363200*a(n-29) -1180887662923776000*a(n-30) +4529957329207296000*a(n-31) +69777190748160000*a(n-32) -5142605210910720000*a(n-33) +1663475920404480000*a(n-34) +2524921315983360000*a(n-35) -1415843728588800000*a(n-36).
%e Some solutions for n=2:
%e 3 6 0 6 0 4 7 5 7 6 6 0 3 7 7 2 2 2 1 4
%e 4 1 1 1 1 4 1 5 1 6 5 5 2 0 6 0 6 0 5 2
%e 3 6 0 6 0 4 7 5 7 6 6 0 3 7 7 1 1 1 0 3
%Y Column 4 of A234712.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 29 2013
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