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%I #8 Jan 26 2019 04:57:22
%S 5,25,120,570,2670,12390,57030,260790,1185990,5368470,24204390,
%T 108756150,487223430,2177121750,9706364070,43188455670,191830083270,
%U 850727111190,3767586342630,16664819732790,73630769405190,325004395216470
%N Number of length-n 0..4 arrays with no repeated value differing from the previous repeated value by other than plus or minus one modulo 4+1.
%H R. H. Hardin, <a href="/A269674/b269674.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) - 6*a(n-2) - 24*a(n-3).
%F Empirical g.f.: 5*x*(1 - 2*x - 5*x^2) / ((1 - 4*x)*(1 - 3*x - 6*x^2)). - _Colin Barker_, Jan 26 2019
%e Some solutions for n=7:
%e ..0. .0. .3. .1. .4. .4. .3. .1. .1. .4. .1. .4. .0. .1. .0. .0
%e ..0. .2. .1. .4. .3. .1. .3. .0. .4. .3. .3. .3. .1. .2. .4. .1
%e ..3. .1. .3. .3. .2. .2. .0. .2. .3. .1. .1. .3. .3. .4. .0. .3
%e ..4. .0. .3. .3. .2. .1. .4. .0. .3. .2. .4. .4. .4. .0. .4. .2
%e ..4. .3. .4. .1. .0. .3. .4. .1. .1. .2. .4. .3. .0. .1. .4. .2
%e ..3. .1. .0. .4. .2. .0. .2. .0. .0. .0. .0. .1. .1. .1. .0. .1
%e ..3. .3. .1. .1. .4. .2. .3. .1. .1. .2. .0. .4. .4. .0. .0. .4
%Y Column 4 of A269678.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 03 2016
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