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%I #7 Nov 28 2016 02:43:28
%S 1,1,2,4,12,40,154,660,3113,15893,86857,502092,3036032,19006591,
%T 122119857,799665333,5308126648,35576413852,240063646519,1627605038848
%N Number of squarefree words of length n in an 8-ary alphabet, with new values 0..7 introduced in increasing order
%C Column 7 of A215075.
%e Some solutions for n=9:
%e ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e ..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....1
%e ..2....2....2....2....2....2....2....2....2....2....2....2....2....2....2....2
%e ..3....0....1....3....1....3....3....1....3....3....0....3....1....1....3....0
%e ..4....3....3....4....3....4....4....3....4....0....3....4....3....3....4....3
%e ..0....1....1....5....4....5....1....0....2....2....4....5....4....0....0....4
%e ..3....4....0....4....0....4....5....4....5....4....5....6....0....1....1....0
%e ..1....2....4....0....2....1....3....2....0....5....1....7....5....0....0....5
%e ..2....0....1....6....3....2....0....5....1....4....6....2....1....3....5....2
%K nonn
%O 1,3
%A _R. H. Hardin_ Aug 02 2012