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%I #7 Jun 19 2022 00:04:40
%S 1328,3688,9656,28400,78824,241456,698304,2200992,6566416,21133848,
%T 64625520,211345224,659476792,2184169416,6931496536,23195106736,
%U 74666215624,252015025392,821113460448,2791657605024,9189851391216
%N Number of (n+1) X (3+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 6, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).
%C Column 3 of A235239.
%H R. H. Hardin, <a href="/A235234/b235234.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) +75*a(n-2) -499*a(n-3) -2477*a(n-4) +18893*a(n-5) +46844*a(n-6) -431641*a(n-7) -544644*a(n-8) +6650508*a(n-9) +3692164*a(n-10) -73169776*a(n-11) -7965360*a(n-12) +593911464*a(n-13) -108754278*a(n-14) -3624939268*a(n-15) +1348847209*a(n-16) +16812874388*a(n-17) -8151710835*a(n-18) -59533275997*a(n-19) +31896084725*a(n-20) +160970283883*a(n-21) -85813326662*a(n-22) -331183400635*a(n-23) +159993289668*a(n-24) +514651400122*a(n-25) -202610873932*a(n-26) -596529887736*a(n-27) +165384664128*a(n-28) +505501523616*a(n-29) -76023552288*a(n-30) -303948460656*a(n-31) +8914601088*a(n-32) +124404317856*a(n-33) +9463220928*a(n-34) -32567277312*a(n-35) -5301282816*a(n-36) +4869517824*a(n-37) +1128950784*a(n-38) -313528320*a(n-39) -89579520*a(n-40).
%e Some solutions for n=4:
%e 5 1 3 1 6 1 6 3 1 3 0 3 2 0 2 0 4 2 3 1
%e 3 5 1 5 3 4 3 6 5 1 4 1 1 5 1 5 1 5 0 4
%e 4 0 2 0 6 1 6 3 4 6 3 6 4 2 4 2 4 2 3 1
%e 3 5 1 5 1 2 1 4 5 1 4 1 0 4 0 4 1 5 0 4
%e 6 2 4 2 6 1 6 3 2 4 1 4 5 3 5 3 5 3 4 2
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2014
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