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Number of length-n 0..7 arrays with no repeated value greater than the previous repeated value.
1

%I #4 Feb 26 2016 07:47:17

%S 8,64,512,4068,32152,252932,1981512,15465934,120310016,933059856,

%T 7216323640,55670133422,428465939112,3290601897928,25221303496496,

%U 192953793764769,1473623863797808,11236105478130612,85542959337048488

%N Number of length-n 0..7 arrays with no repeated value greater than the previous repeated value.

%C Column 7 of A269435.

%H R. H. Hardin, <a href="/A269434/b269434.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 56*a(n-1) -1364*a(n-2) +18816*a(n-3) -159866*a(n-4) +846328*a(n-5) -2642416*a(n-6) +3954888*a(n-7) -157507*a(n-8) -3954888*a(n-9) -2642416*a(n-10) -846328*a(n-11) -159866*a(n-12) -18816*a(n-13) -1364*a(n-14) -56*a(n-15) -a(n-16)

%e Some solutions for n=5

%e ..6. .2. .3. .3. .2. .7. .4. .6. .2. .5. .1. .4. .5. .5. .4. .1

%e ..5. .2. .3. .5. .3. .0. .0. .5. .6. .3. .7. .1. .3. .5. .0. .2

%e ..2. .3. .5. .7. .1. .3. .4. .1. .2. .7. .1. .3. .6. .1. .7. .5

%e ..1. .1. .1. .1. .6. .1. .3. .5. .1. .1. .6. .7. .0. .0. .6. .0

%e ..0. .5. .7. .7. .5. .0. .5. .3. .3. .5. .5. .7. .6. .3. .2. .1

%Y Cf. A269435.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 26 2016