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%I #7 Jan 23 2019 07:18:50
%S 14,174,852,2780,7170,15834,31304,56952,97110,157190,243804,364884,
%T 529802,749490,1036560,1405424,1872414,2455902,3176420,4056780,
%U 5122194,6400394,7921752,9719400,11829350,14290614,17145324,20438852,24219930
%N Number of length-5 0..n arrays with no repeated value equal to the previous repeated value.
%H R. H. Hardin, <a href="/A269469/b269469.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = n^5 + 5*n^4 + 7*n^3 + 2*n^2 - n.
%F Conjectures from _Colin Barker_, Jan 23 2019: (Start)
%F G.f.: 2*x*(7 + 45*x + 9*x^2 - x^3) / (1 - x)^6.
%F a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
%F (End)
%e Some solutions for n=3:
%e ..0. .1. .1. .3. .3. .2. .0. .3. .2. .2. .0. .3. .3. .2. .1. .1
%e ..3. .1. .3. .2. .3. .2. .3. .1. .0. .1. .1. .3. .2. .3. .2. .3
%e ..1. .2. .0. .3. .0. .1. .1. .3. .0. .0. .3. .0. .2. .2. .1. .2
%e ..0. .2. .3. .0. .3. .3. .2. .2. .1. .0. .3. .1. .1. .3. .2. .1
%e ..3. .0. .3. .2. .2. .3. .3. .2. .1. .2. .0. .2. .0. .3. .2. .3
%Y Row 5 of A269467.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 27 2016
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