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A243604 Number of length n+2 0..7 arrays with no three elements in a row with pattern aba (with a!=b) and new values 0..7 introduced in 0..7 order.

%I A243604 #6 Jul 23 2025 11:21:02
%S A243604 4,10,29,97,366,1534,7049,35129,187993,1069914,6413136,40104257,
%T A243604 259358085,1721368017,11650893890,80015045418,555433766065,
%U A243604 3885803906493,27339242339942,193138394368496,1368463903086546,9716805805575427
%N A243604 Number of length n+2 0..7 arrays with no three elements in a row with pattern aba (with a!=b) and new values 0..7 introduced in 0..7 order.
%C A243604 Column 7 of A243607
%H A243604 R. H. Hardin, <a href="/A243604/b243604.txt">Table of n, a(n) for n = 1..210</a>
%F A243604 Empirical: a(n) = 23*a(n-1) -206*a(n-2) +894*a(n-3) -1814*a(n-4) +902*a(n-5) +1940*a(n-6) -1536*a(n-7) -1306*a(n-8) +394*a(n-9) +526*a(n-10) +162*a(n-11) +21*a(n-12) +a(n-13)
%e A243604 Some solutions for n=5
%e A243604 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A243604 ..1....1....1....0....1....0....1....1....0....1....1....1....1....1....0....1
%e A243604 ..2....2....2....1....1....0....2....2....1....2....2....2....2....1....1....2
%e A243604 ..3....0....2....2....2....0....3....2....2....3....3....0....2....2....2....3
%e A243604 ..3....1....0....2....2....1....0....3....2....1....1....0....3....3....0....1
%e A243604 ..3....2....1....3....1....1....2....1....1....0....4....0....1....0....1....0
%e A243604 ..4....0....2....3....1....1....2....4....1....4....2....2....1....1....2....2
%K A243604 nonn
%O A243604 1,1
%A A243604 _R. H. Hardin_, Jun 07 2014