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%I #6 Jun 20 2022 00:40:57
%S 16848,74308,329984,1558600,7424496,37338544,189345872,1006857472,
%T 5389971408,30077051488,168561386384,979772704480,5704468149456,
%U 34304416485664,206090647457552,1274575646527072,7855291807049808
%N Number of (n+1) X (3+1) 0..7 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="/A234699/b234699.txt">Table of n, a(n) for n = 1..186</a>
%F Empirical: a(n) = 20*a(n-1) +141*a(n-2) -5340*a(n-3) +5451*a(n-4) +616740*a(n-5) -2678805*a(n-6) -39706740*a(n-7) +278440182*a(n-8) +1491646680*a(n-9) -16092380232*a(n-10) -27470360160*a(n-11) +601403119168*a(n-12) -194332088960*a(n-13) -15257818574160*a(n-14) +26729605928640*a(n-15) +263906583339744*a(n-16) -801813357648000*a(n-17) -2982678610973184*a(n-18) +13948745101747200*a(n-19) +18588639920403456*a(n-20) -156794289434542080*a(n-21) -1681574850293760*a(n-22) +1140373919202508800*a(n-23) -1022866437252096000*a(n-24) -5015897891205120000*a(n-25) +8536532135362560000*a(n-26) +10656426280550400000*a(n-27) -31534442652303360000*a(n-28) +815374290124800000*a(n-29) +46191901645209600000*a(n-30) -31856483893248000000*a(n-31).
%e Some solutions for n=2:
%e 7 1 6 5 5 5 5 0 6 5 6 5 6 0 3 2 5 0 3 3
%e 2 1 1 5 7 2 7 7 2 6 2 6 5 4 2 6 7 7 5 0
%e 3 7 2 1 1 1 1 6 3 2 3 2 7 1 4 3 6 1 4 4
%Y Column 3 of A234702.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 29 2013