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Number of length n arrays of permutations of 0..n-1 with each element moved by -5 to 5 places and with no two consecutive increases or two consecutive decreases.
1

%I #4 Oct 23 2015 11:20:46

%S 1,2,4,10,32,122,422,1222,3302,9021,24558,69453,198750,569814,1618526,

%T 4609110,13012670,36977018,104466558,297190402,840584030,2392121298,

%U 6764980670,19248138770,54423938014,154841629474,437824909566

%N Number of length n arrays of permutations of 0..n-1 with each element moved by -5 to 5 places and with no two consecutive increases or two consecutive decreases.

%C Column 5 of A263666.

%H R. H. Hardin, <a href="/A263663/b263663.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-2) +14*a(n-4) +58*a(n-6) +216*a(n-8) +36*a(n-10) -504*a(n-12) +128*a(n-14) -448*a(n-18) +384*a(n-20) -64*a(n-22) for n>34

%e Some solutions for n=7

%e ..3....2....2....3....3....0....0....0....2....5....3....5....1....3....1....2

%e ..4....6....0....1....4....5....6....5....5....6....1....6....5....1....6....5

%e ..1....1....5....4....1....1....3....2....1....2....5....1....2....2....0....0

%e ..5....4....1....0....2....4....4....3....6....4....4....4....4....0....4....6

%e ..0....0....6....5....0....2....1....1....0....0....6....0....0....6....3....3

%e ..6....5....3....2....6....6....5....6....4....3....0....3....6....4....5....4

%e ..2....3....4....6....5....3....2....4....3....1....2....2....3....5....2....1

%Y Cf. A263666.

%K nonn

%O 1,2

%A _R. H. Hardin_, Oct 23 2015