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A249704 Number of length n+3 0..5 arrays with every four consecutive terms having the maximum of some two terms equal to the minimum of the remaining two terms.

%I A249704 #6 Jul 23 2025 12:06:11
%S A249704 366,966,2524,6172,13666,32500,80360,198164,474302,1140694,2782978,
%T A249704 6829394,16652268,40525818,98972744,242571962,594328514,1454961448,
%U A249704 3564476384,8746203338,21475833432,52737244176,129543959312,318439317418
%N A249704 Number of length n+3 0..5 arrays with every four consecutive terms having the maximum of some two terms equal to the minimum of the remaining two terms.
%C A249704 Column 5 of A249707
%H A249704 R. H. Hardin, <a href="/A249704/b249704.txt">Table of n, a(n) for n = 1..210</a>
%F A249704 Empirical: a(n) = 3*a(n-1) -3*a(n-2) +a(n-3) +45*a(n-4) -80*a(n-5) +35*a(n-6) -757*a(n-8) +513*a(n-9) +28*a(n-10) +28*a(n-11) +6071*a(n-12) +1434*a(n-13) +314*a(n-14) -486*a(n-15) -26788*a(n-16) -25212*a(n-17) -13792*a(n-18) -4416*a(n-19) +68776*a(n-20) +102232*a(n-21) +67200*a(n-22) +29760*a(n-23) -93984*a(n-24) -186624*a(n-25) -130176*a(n-26) -43776*a(n-27) +69120*a(n-28) +138240*a(n-29) +69120*a(n-30)
%e A249704 Some solutions for n=6
%e A249704 ..1....3....2....5....0....1....2....2....0....2....5....1....4....2....0....2
%e A249704 ..1....1....3....4....4....5....4....3....4....3....2....2....4....2....5....4
%e A249704 ..3....3....3....4....5....1....2....5....5....0....1....4....3....2....4....1
%e A249704 ..1....3....3....4....4....0....0....3....4....2....2....2....5....0....4....2
%e A249704 ..0....3....3....4....3....1....2....3....4....2....3....2....4....2....1....2
%e A249704 ..1....3....3....4....4....3....5....3....4....5....2....2....4....4....4....2
%e A249704 ..5....2....4....0....4....1....2....3....4....2....2....2....1....2....4....2
%e A249704 ..1....4....1....5....5....1....0....1....4....0....2....4....5....0....5....0
%e A249704 ..0....3....3....4....1....0....2....4....3....2....3....1....4....2....2....3
%K A249704 nonn
%O A249704 1,1
%A A249704 _R. H. Hardin_, Nov 04 2014