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%I #4 Nov 23 2013 07:31:04
%S 8,296,4404,63744,957232,14297980,213082596,3180405572,47457708756,
%T 708101568772,10565916295512,157657615301852,2352456485793908,
%U 35101771262909316,523764821849080236,7815262731268162904
%N Number of nX4 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal
%C Column 4 of A232376
%H R. H. Hardin, <a href="/A232372/b232372.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 10*a(n-1) +46*a(n-2) +374*a(n-3) +330*a(n-4) +2418*a(n-5) +7211*a(n-6) +9104*a(n-7) +1944*a(n-8) -21557*a(n-9) -54205*a(n-10) -77028*a(n-11) -83393*a(n-12) -57615*a(n-13) -34140*a(n-14) -9235*a(n-15) -944*a(n-16) +2734*a(n-17) +385*a(n-18) +30*a(n-19) -35*a(n-20) +138*a(n-21) -4*a(n-22)
%e Some solutions for n=4
%e ..1..0..3..2....1..0..1..0....1..2..1..0....2..3..0..3....0..3..0..3
%e ..3..2..1..2....3..2..1..0....1..2..3..0....0..1..2..1....2..1..2..3
%e ..1..2..1..3....3..0..1..0....3..2..1..2....2..3..0..1....0..1..0..1
%e ..3..2..1..3....3..2..1..3....3..0..3..0....2..1..2..1....0..3..2..3
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 23 2013