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Number of length n arrays x(i), i=1..n with x(i) in i..i+5 and no value appearing more than 3 times
1

%I #4 Nov 19 2014 15:59:25

%S 6,36,216,1293,7712,45866,272760,1621963,9644496,57346376,340979312,

%T 2027446948,12055094608,71678940042,426199029864,2534155836542,

%U 15067950109140,89593195408640,532716168060704,3167500770096043

%N Number of length n arrays x(i), i=1..n with x(i) in i..i+5 and no value appearing more than 3 times

%C Column 5 of A250361

%H R. H. Hardin, <a href="/A250358/b250358.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) -4*a(n-4) -22*a(n-5) -130*a(n-6) +7*a(n-8) +50*a(n-9) +66*a(n-10) +a(n-12) -6*a(n-13)

%e Some solutions for n=6

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

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

%e ..7....6....5....7....6....6....4....7....4....7....2....7....3....7....3....2

%e ..6....6....4....8....6....8....8....4....6....6....8....7....3....4....7....6

%e ..4....6....5....4....9....7....8....8....4....5....9....9....6....4....6....7

%e .10....8....9....6....5....6....8....6...10....7....8....5....9....8....7....7

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 19 2014