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%I #8 Jan 23 2019 10:07:40
%S 6,36,216,1286,7616,44904,263794,1545030,9026500,52624694,306261764,
%T 1779708548,10328981458,59882754332,346857774682,2007544602552,
%U 11611615811212,67123684593712,387837889353322,2239991195959860
%N Number of length-n 0..5 arrays with no repeated value differing from the previous repeated value by one.
%H R. H. Hardin, <a href="/A269491/b269491.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 20*a(n-1) - 145*a(n-2) + 425*a(n-3) - 252*a(n-4) - 605*a(n-5) - 53*a(n-6) + 15*a(n-7).
%F Empirical g.f.: 2*x*(3 - 42*x + 183*x^2 - 182*x^3 - 286*x^4 - 22*x^5 + 7*x^6) / ((1 - 5*x)*(1 - 15*x + 70*x^2 - 75*x^3 - 123*x^4 - 10*x^5 + 3*x^6)). - _Colin Barker_, Jan 23 2019
%e Some solutions for n=6:
%e ..0. .3. .5. .4. .2. .5. .4. .1. .0. .5. .5. .0. .2. .0. .0. .3
%e ..1. .0. .5. .3. .0. .4. .5. .5. .2. .0. .0. .3. .4. .0. .0. .1
%e ..0. .4. .2. .1. .0. .2. .1. .1. .1. .5. .3. .5. .5. .5. .5. .3
%e ..5. .4. .5. .5. .3. .0. .3. .4. .2. .2. .1. .5. .2. .5. .3. .1
%e ..5. .0. .2. .3. .1. .5. .1. .5. .0. .3. .2. .2. .5. .3. .0. .4
%e ..2. .4. .2. .4. .0. .4. .0. .0. .1. .1. .0. .3. .2. .5. .2. .2
%Y Column 5 of A269494.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 28 2016