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Number of nX5 0..3 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4 and at least one element with value (x(i,j)-1) mod 4, no adjacent elements equal, and upper left element zero
1

%I #4 Nov 03 2013 07:13:57

%S 0,100,644,20050,344136,7293728,142466422,2871061676,57167235796,

%T 1143545760606,22834586760592,456274562629780,9114796829043214,

%U 182100336288975336,3637960938217657028,72679448308125342402

%N Number of nX5 0..3 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4 and at least one element with value (x(i,j)-1) mod 4, no adjacent elements equal, and upper left element zero

%C Column 5 of A231049

%H R. H. Hardin, <a href="/A231046/b231046.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 12*a(n-1) +161*a(n-2) +479*a(n-3) -6440*a(n-4) -76243*a(n-5) -10558*a(n-6) +451344*a(n-7) +2020488*a(n-8) -2582232*a(n-9) +385720*a(n-10) -11411116*a(n-11) +16317478*a(n-12) -7836152*a(n-13) +22258694*a(n-14) -43868182*a(n-15) +22620856*a(n-16) -14534462*a(n-17) +58185316*a(n-18) -20490672*a(n-19) -20508996*a(n-20) -30191252*a(n-21) +1794712*a(n-22) +8269896*a(n-23) +5870551*a(n-24) +2241164*a(n-25) -96667*a(n-26) -21533*a(n-27) -650816*a(n-28) -264235*a(n-29) -125314*a(n-30) +61088*a(n-31) +29008*a(n-32) +12576*a(n-33) -1024*a(n-34) -192*a(n-35) -128*a(n-36)

%e Some solutions for n=4

%e ..0..1..2..3..0....0..1..2..1..2....0..3..0..3..2....0..1..2..1..0

%e ..0..3..2..1..2....2..3..2..3..0....2..1..0..1..0....0..3..0..3..0

%e ..0..3..0..3..0....2..1..2..1..2....0..3..0..1..2....2..1..0..3..2

%e ..0..1..2..1..2....2..3..0..3..2....2..1..0..3..2....2..3..0..1..0

%K nonn

%O 1,2

%A _R. H. Hardin_, Nov 03 2013