cp's OEIS Frontend

A221570 Number of 0..5 arrays of length n with each element differing from at least one neighbor by something other than 1.

%I A221570 #9 Jun 02 2025 08:21:38
%S A221570 0,26,114,676,3734,20944,117104,655198,3665306,20505052,114711980,
%T A221570 641737294,3590092664,20084178100,112357602542,628565969692,
%U A221570 3516408049766,19671961528672,110051525562128,615665004273436
%N A221570 Number of 0..5 arrays of length n with each element differing from at least one neighbor by something other than 1.
%C A221570 Column 5 of A221573
%H A221570 R. H. Hardin, <a href="/A221570/b221570.txt">Table of n, a(n) for n = 1..210</a>
%F A221570 Empirical: a(n) = 5*a(n-1) +3*a(n-2) +9*a(n-4) +6*a(n-5) +3*a(n-6).
%F A221570 Empirical g.f.: -2*x^2*(13-8*x+14*x^2+6*x^3+6*x^4) / ( -1+5*x+3*x^2+9*x^4+6*x^5+3*x^6 ). - _R. J. Mathar_, Jun 06 2013
%e A221570 Some solutions for n=6
%e A221570 ..4....0....4....1....2....5....4....4....2....0....0....1....1....3....0....3
%e A221570 ..0....5....2....3....4....2....0....4....5....3....5....4....3....5....3....5
%e A221570 ..0....2....4....5....0....5....0....0....4....5....0....1....0....2....0....1
%e A221570 ..1....5....5....3....1....4....2....3....1....4....3....2....1....4....3....3
%e A221570 ..3....1....0....1....4....1....1....1....0....2....2....2....5....2....0....3
%e A221570 ..1....5....5....5....0....3....4....5....4....0....2....4....3....5....0....1
%K A221570 nonn
%O A221570 1,2
%A A221570 _R. H. Hardin_ Jan 20 2013