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%I #8 Jan 24 2019 17:26:26
%S 5,25,120,572,2692,12570,58280,268704,1233046,5636046,25675580,
%T 116635916,528551090,2390183046,10789164304,48625122028,218845692934,
%U 983773248134,4417701453060,19819733378212,88847987191058,398004177820814
%N Number of length-n 0..4 arrays with no repeated value differing from the previous repeated value by one or less.
%H R. H. Hardin, <a href="/A269602/b269602.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 13*a(n-1) - 49*a(n-2) - 5*a(n-3) + 292*a(n-4) - 70*a(n-5) - 658*a(n-6) - 344*a(n-7).
%F Empirical g.f.: x*(5 - 40*x + 40*x^2 + 262*x^3 - 199*x^4 - 748*x^5 - 362*x^6) / ((1 - 4*x)*(1 - 9*x + 13*x^2 + 57*x^3 - 64*x^4 - 186*x^5 - 86*x^6)). - _Colin Barker_, Jan 24 2019
%e Some solutions for n=7:
%e ..0. .1. .1. .4. .3. .2. .1. .2. .1. .2. .4. .4. .1. .3. .4. .1
%e ..1. .0. .4. .1. .1. .1. .4. .4. .1. .3. .2. .1. .4. .4. .1. .1
%e ..4. .0. .4. .0. .0. .0. .1. .1. .2. .0. .2. .4. .0. .3. .0. .2
%e ..4. .4. .2. .1. .0. .1. .1. .1. .3. .3. .4. .4. .1. .2. .4. .1
%e ..0. .4. .4. .3. .2. .0. .3. .2. .2. .1. .2. .2. .1. .2. .2. .3
%e ..1. .2. .3. .1. .3. .3. .4. .1. .0. .0. .4. .3. .2. .0. .1. .1
%e ..3. .4. .1. .0. .1. .4. .4. .3. .4. .3. .0. .2. .4. .3. .0. .4
%Y Column 4 of A269606.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 01 2016
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