A212828 - OEIS

%I #4 May 28 2012 08:35:10

%S 1,2,5,13,44,168,717,3360,17091,93492,545670,3372738,21911216,

%T 148486735,1041923520,7518618028,55460237723,416078640459,

%U 3161904730760,24261222270154,187499556005523,1456815538485716,11363752138036864

%N Number of 0..7 arrays of length n with no adjacent pair equal to its immediately preceding adjacent pair, and new values introduced in 0..7 order

%C Column 7 of A212829

%H R. H. Hardin, <a href="/A212828/b212828.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) for n>15

%e Some solutions for n=8

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

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

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

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

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

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_ May 28 2012