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Number of length n arrays of permutations of 0..n-1 with each element moved by -3 to 3 places and every four consecutive elements having its maximum within 4 of its minimum.
1

%I #8 Jan 02 2019 23:12:32

%S 1,2,6,24,78,60,50,52,70,116,184,292,449,649,969,1429,2137,3238,4839,

%T 7285,10924,16339,24553,36769,55153,82769,124024,186099,279039,418384,

%U 627613,940985,1411273,2116505,3173705,4759874,7137847,10704221,16053112

%N Number of length n arrays of permutations of 0..n-1 with each element moved by -3 to 3 places and every four consecutive elements having its maximum within 4 of its minimum.

%H R. H. Hardin, <a href="/A263712/b263712.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +a(n-3) -a(n-4) +2*a(n-5) -a(n-6) +a(n-7) for n>18.

%F Empirical g.f.: x*(1 + x + 4*x^2 + 17*x^3 + 53*x^4 - 24*x^5 - 31*x^6 - 63*x^7 - 8*x^8 - 82*x^9 - 28*x^11 - 3*x^12 - 6*x^13 - 2*x^14 - 19*x^15 - 8*x^16 - 9*x^17) / (1 - x - x^3 + x^4 - 2*x^5 + x^6 - x^7). - _Colin Barker_, Jan 02 2019

%e Some solutions for n=7:

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

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

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

%e ..4....4....4....4....2....4....2....3....3....3....2....2....2....4....2....4

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

%e ..6....5....6....5....6....5....5....6....2....6....6....3....5....5....6....5

%e ..5....6....5....6....5....6....6....4....6....5....3....6....6....6....5....6

%Y Column 3 of A263714.

%K nonn

%O 1,2

%A _R. H. Hardin_, Oct 24 2015