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Number of length n+3 0..5 arrays with no four elements in a row with pattern aabb (with a!=b) and new values 0..5 introduced in 0..5 order
1

%I #4 May 17 2014 19:19:40

%S 14,46,175,744,3453,17178,90033,489821,2734513,15534111,89271482,

%T 516935609,3008249095,17562798942,102750973652,601965097333,

%U 3529737223262,20709247799845,121548480504365,713577294998844

%N Number of length n+3 0..5 arrays with no four elements in a row with pattern aabb (with a!=b) and new values 0..5 introduced in 0..5 order

%C Column 5 of A242584

%H R. H. Hardin, <a href="/A242581/b242581.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 16*a(n-1) -106*a(n-2) +425*a(n-3) -1284*a(n-4) +3083*a(n-5) -5823*a(n-6) +9091*a(n-7) -11623*a(n-8) +11784*a(n-9) -9883*a(n-10) +6151*a(n-11) -2730*a(n-12) +900*a(n-13)

%e Some solutions for n=4

%e ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

%e ..0....1....1....1....1....1....1....1....1....1....1....1....1....0....1....0

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

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

%e ..3....1....1....4....3....0....2....2....1....0....2....0....3....2....0....1

%e ..2....2....2....5....1....2....2....1....0....2....3....1....1....3....2....2

%e ..0....1....3....4....4....2....0....3....2....1....1....0....1....1....2....3

%K nonn

%O 1,1

%A _R. H. Hardin_, May 17 2014