A242470 - OEIS

%I #4 May 15 2014 19:18:59

%S 4,12,41,159,685,3233,16533,90817,531812,3295779,21456363,145645809,

%T 1023308083,7391587656,54563960012,409583330514,3113836080693,

%U 23899707589707,184747234605277,1435668152296255,11200152289621048

%N Number of length n+2 0..7 arrays with no three equal elements in a row and new values 0..7 introduced in 0..7 order

%C Column 7 of A242472

%H R. H. Hardin, <a href="/A242470/b242470.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 22*a(n-1) -168*a(n-2) +440*a(n-3) +421*a(n-4) -2898*a(n-5) -924*a(n-6) +7944*a(n-7) +5931*a(n-8) -6610*a(n-9) -10562*a(n-10) -5040*a(n-11) -840*a(n-12)

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, May 15 2014