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%I #8 Jan 29 2019 05:49:52
%S 8,64,512,4088,32592,259504,2063880,16398144,130175360,1032602872,
%T 8185566032,64850011184,513508842504,4064330589760,32155606323456,
%U 254314670475768,2010717722177360,15893207240651440,125593338184358408
%N Number of length-n 0..7 arrays with every repeated value unequal to the previous repeated value plus one mod 7+1.
%H R. H. Hardin, <a href="/A269775/b269775.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 14*a(n-1) - 42*a(n-2) -49*a(n-3).
%F Empirical g.f.: 8*x*(1 - 6*x - 6*x^2) / ((1 - 7*x)*(1 - 7*x - 7*x^2)). - _Colin Barker_, Jan 29 2019
%e Some solutions for n=5:
%e ..4. .2. .0. .1. .2. .0. .2. .7. .4. .3. .1. .0. .7. .5. .5. .6
%e ..3. .3. .0. .1. .2. .5. .0. .1. .7. .1. .0. .5. .1. .2. .1. .6
%e ..4. .2. .6. .0. .6. .5. .0. .1. .1. .5. .3. .2. .5. .6. .7. .6
%e ..3. .0. .1. .4. .4. .1. .7. .5. .3. .3. .3. .4. .3. .1. .1. .5
%e ..5. .1. .5. .1. .0. .4. .5. .5. .0. .1. .3. .0. .1. .1. .2. .7
%Y Column 7 of A269776.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 04 2016