cp's OEIS Frontend

A212828 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.

%I A212828 #6 Jul 22 2025 22:58:10
%S A212828 1,2,5,13,44,168,717,3360,17091,93492,545670,3372738,21911216,
%T A212828 148486735,1041923520,7518618028,55460237723,416078640459,
%U A212828 3161904730760,24261222270154,187499556005523,1456815538485716,11363752138036864
%N A212828 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 A212828 Column 7 of A212829
%H A212828 R. H. Hardin, <a href="/A212828/b212828.txt">Table of n, a(n) for n = 1..210</a>
%F A212828 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 A212828 Some solutions for n=8
%e A212828 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A212828 ..1....0....1....1....1....1....1....1....1....1....1....1....1....0....0....1
%e A212828 ..2....1....2....2....2....0....1....0....2....1....1....2....2....1....1....1
%e A212828 ..2....1....1....0....2....2....2....2....3....0....0....3....3....2....2....2
%e A212828 ..3....1....3....1....0....0....1....3....2....1....2....3....0....1....1....1
%e A212828 ..4....2....2....2....2....3....3....0....4....2....1....0....1....1....1....1
%e A212828 ..3....3....4....1....1....3....4....0....1....1....0....1....4....1....3....2
%e A212828 ..5....0....4....0....0....4....4....0....4....0....0....3....4....3....0....2
%K A212828 nonn
%O A212828 1,2
%A A212828 _R. H. Hardin_ May 28 2012