A242582 - OEIS

%I #6 Jul 23 2025 11:18:08

%S 14,46,175,745,3481,17634,95729,550503,3316400,20716789,133010422,

%T 871426139,5793393075,38920526974,263416849112,1792161569676,

%U 12237842678789,83782031880589,574620337324485,3946034125700132

%N Number of length n+3 0..6 arrays with no four elements in a row with pattern aabb (with a!=b) and new values 0..6 introduced in 0..6 order.

%C Column 6 of A242584

%H R. H. Hardin, <a href="/A242582/b242582.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 22*a(n-1) -206*a(n-2) +1156*a(n-3) -4714*a(n-4) +15358*a(n-5) -40643*a(n-6) +89400*a(n-7) -167115*a(n-8) +262308*a(n-9) -349485*a(n-10) +393316*a(n-11) -361252*a(n-12) +276048*a(n-13) -160848*a(n-14) +67392*a(n-15) -20736*a(n-16)

%e Some solutions for n=4

%e ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

%e ..1....0....0....1....1....1....0....1....0....1....0....1....1....1....1....1

%e ..0....0....1....1....1....2....0....2....1....2....1....0....2....0....2....2

%e ..1....1....2....2....1....3....0....3....0....0....2....2....3....2....3....3

%e ..2....2....3....0....2....1....0....0....0....3....3....0....0....0....0....4

%e ..1....3....1....0....0....0....0....3....0....4....2....3....2....2....1....2

%e ..1....4....0....3....1....1....0....2....2....1....3....4....0....1....3....5

%K nonn

%O 1,1

%A _R. H. Hardin_, May 17 2014