cp's OEIS Frontend

A268953 Number of length-n 0..5 arrays with no repeated value equal to the previous repeated value, with new values introduced in sequential order.

%I A268953 #4 Feb 16 2016 11:49:14
%S A268953 1,2,4,12,40,154,655,3045,15124,78930,426289,2355975,13216982,
%T A268953 74856340,426491859,2438853865,13977348104,80210943670,460646222293,
%U A268953 2646524858907,15207848530170,87395420173144,502235483752631,2886069610014893
%N A268953 Number of length-n 0..5 arrays with no repeated value equal to the previous repeated value, with new values introduced in sequential order.
%C A268953 Column 5 of A268956.
%H A268953 R. H. Hardin, <a href="/A268953/b268953.txt">Table of n, a(n) for n = 1..210</a>
%F A268953 Empirical: a(n) = 18*a(n-1) -110*a(n-2) +170*a(n-3) +801*a(n-4) -2920*a(n-5) -662*a(n-6) +12700*a(n-7) -6980*a(n-8) -22928*a(n-9) +19192*a(n-10) +15120*a(n-11) -14400*a(n-12) for n>14
%e A268953 Some solutions for n=8
%e A268953 ..0. .0. .0. .0. .0. .0. .0. .0. .0. .0. .0. .0. .0. .0. .0. .0
%e A268953 ..1. .1. .1. .1. .0. .1. .1. .0. .1. .1. .1. .1. .1. .1. .1. .0
%e A268953 ..0. .2. .0. .0. .1. .2. .0. .1. .2. .1. .1. .2. .1. .0. .2. .1
%e A268953 ..1. .3. .0. .2. .0. .0. .2. .2. .0. .2. .2. .2. .2. .1. .3. .2
%e A268953 ..1. .3. .2. .0. .2. .2. .1. .2. .3. .0. .3. .3. .1. .1. .4. .1
%e A268953 ..2. .4. .1. .1. .2. .3. .0. .3. .3. .3. .1. .1. .0. .0. .4. .0
%e A268953 ..2. .0. .3. .0. .3. .2. .0. .1. .1. .4. .3. .2. .3. .2. .1. .3
%e A268953 ..3. .4. .0. .0. .1. .1. .1. .0. .0. .3. .1. .0. .1. .0. .1. .0
%Y A268953 Cf. A268956.
%K A268953 nonn
%O A268953 1,2
%A A268953 _R. H. Hardin_, Feb 16 2016