cp's OEIS Frontend

A269532 Number of length-n 0..3 arrays with no repeated value differing from the previous repeated value by other than one.

%I A269532 #7 Mar 21 2018 15:13:24
%S A269532 4,16,60,222,804,2878,10192,35812,125012,434110,1500912,5170626,
%T A269532 17758812,60837880,207965356,709583398,2417278172,8223508510,
%U A269532 27943213944,94853465148,321696510276,1090199408374,3692112980824,12496559933794
%N A269532 Number of length-n 0..3 arrays with no repeated value differing from the previous repeated value by other than one.
%C A269532 Column 3 of A269537.
%H A269532 R. H. Hardin, <a href="/A269532/b269532.txt">Table of n, a(n) for n = 1..210</a>
%F A269532 Empirical: a(n) = 7*a(n-1) - 9*a(n-2) - 23*a(n-3) + 31*a(n-4) + 33*a(n-5).
%F A269532 Empirical g.f.: 2*x*(2 - 6*x - 8*x^2 + 19*x^3 + 17*x^4) / ((1 - 3*x)*(1 - 4*x - 3*x^2 + 14*x^3 + 11*x^4)). - _Colin Barker_, Mar 21 2018
%e A269532 Some solutions for n=9:
%e A269532 ..2. .1. .0. .0. .3. .0. .1. .2. .1. .2. .0. .1. .1. .0. .0. .1
%e A269532 ..1. .3. .3. .0. .0. .2. .2. .2. .0. .0. .3. .2. .3. .3. .2. .2
%e A269532 ..0. .0. .2. .1. .3. .3. .0. .0. .3. .1. .0. .0. .1. .3. .0. .1
%e A269532 ..2. .3. .2. .1. .2. .2. .1. .3. .1. .2. .0. .2. .0. .0. .3. .3
%e A269532 ..2. .0. .3. .0. .0. .0. .0. .2. .0. .3. .2. .3. .3. .3. .2. .3
%e A269532 ..3. .2. .0. .0. .3. .1. .0. .0. .2. .0. .3. .1. .3. .0. .0. .0
%e A269532 ..1. .1. .3. .2. .2. .0. .3. .3. .2. .3. .2. .2. .1. .2. .1. .1
%e A269532 ..1. .2. .0. .3. .3. .0. .1. .2. .0. .2. .1. .2. .2. .1. .2. .0
%e A269532 ..3. .3. .3. .0. .0. .1. .3. .3. .3. .2. .2. .0. .2. .2. .1. .2
%Y A269532 Cf. A269537.
%K A269532 nonn
%O A269532 1,1
%A A269532 _R. H. Hardin_, Feb 29 2016