%I #7 Jun 19 2022 00:04:44
%S 4652,11728,28400,77368,201676,580668,1593940,4773744,13619216,
%T 41986384,123455548,389051892,1172319572,3758507320,11558458656,
%U 37574720456,117559819820,386585266780,1227444437620,4075831706064,13106397783216
%N Number of (n+1) X (4+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 4 of A235239.
%H R. H. Hardin, <a href="/A235235/b235235.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) +69*a(n-2) -574*a(n-3) -1978*a(n-4) +21370*a(n-5) +27951*a(n-6) -478485*a(n-7) -113003*a(n-8) +7195152*a(n-9) -2958344*a(n-10) -76861940*a(n-11) +65204416*a(n-12) +601876824*a(n-13) -702665742*a(n-14) -3516184990*a(n-15) +4973786477*a(n-16) +15464027179*a(n-17) -24964585223*a(n-18) -51381565162*a(n-19) +91429360722*a(n-20) +129074199158*a(n-21) -246783610545*a(n-22) -245370073973*a(n-23) +491176690303*a(n-24) +354658110454*a(n-25) -717262274054*a(n-26) -393919013804*a(n-27) +761914551864*a(n-28) +340116859488*a(n-29) -581525075904*a(n-30) -227924908368*a(n-31) +312863061744*a(n-32) +115489716768*a(n-33) -114941096928*a(n-34) -42030498240*a(n-35) +27265994496*a(n-36) +10170800640*a(n-37) -3740567040*a(n-38) -1442479104*a(n-39) +223948800*a(n-40) +89579520*a(n-41).
%e Some solutions for n=4:
%e 5 0 3 1 4 5 2 5 3 6 2 6 1 6 2 5 1 4 1 6
%e 4 5 2 6 3 1 4 1 5 2 3 1 2 1 3 1 3 0 3 2
%e 5 0 3 1 4 5 2 5 3 6 2 6 1 6 2 4 0 3 0 5
%e 4 5 2 6 3 0 3 0 4 1 5 3 4 3 5 3 5 2 5 4
%e 6 1 4 2 5 3 0 3 1 4 1 5 0 5 1 5 1 4 1 6
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2014
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