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%I #7 Jan 24 2019 11:45:03
%S 5,25,125,613,2969,14239,67763,320495,1508267,7069055,33020571,
%T 153815099,714838023,3315709471,15354722091,71009625019,328017083175,
%U 1513765237255,6980228317107,32165146949139,148133524803711,681887792337519
%N Number of length-n 0..4 arrays with no repeated value differing from the previous repeated value by more than one.
%H R. H. Hardin, <a href="/A269579/b269579.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 16*a(n-1) - 93*a(n-2) + 220*a(n-3) - 112*a(n-4) - 192*a(n-5) - 2*a(n-6) + 8*a(n-7).
%F Empirical g.f.: x*(5 - 55*x + 190*x^2 - 162*x^3 - 154*x^4 + 4*x^5 + 6*x^6) / ((1 - 4*x)*(1 - 4*x - x^2)*(1 - 8*x + 14*x^2 + 8*x^3 - 2*x^4)). - _Colin Barker_, Jan 24 2019
%e Some solutions for n=6:
%e ..3. .4. .0. .0. .0. .3. .0. .2. .2. .2. .4. .4. .1. .3. .1. .2
%e ..1. .1. .3. .4. .4. .0. .4. .4. .3. .3. .2. .3. .4. .0. .0. .4
%e ..3. .0. .4. .0. .2. .4. .1. .2. .4. .2. .0. .2. .0. .0. .1. .4
%e ..4. .3. .0. .4. .3. .3. .0. .0. .2. .4. .3. .3. .1. .1. .0. .3
%e ..4. .0. .2. .4. .2. .2. .4. .2. .2. .1. .1. .1. .1. .3. .4. .3
%e ..4. .1. .0. .2. .4. .3. .0. .0. .0. .3. .3. .4. .4. .0. .4. .2
%Y Column 4 of A269583.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 01 2016
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