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%I #9 Dec 12 2015 01:46:45
%S 1,1,1,3,6,27,99,463,2233,11875,66925,402364,2555606,17115329,
%T 120368115,886510373,6819231506
%N Number of length-n 0..n arrays connected end-around, with no sequence of L<n elements immediately followed by itself (periodic "squarefree"), and new values introduced in order 0..n.
%C Diagonal of A215401.
%e Some solutions for n=6:
%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....0....0....2....2....2....2....2....0....2....2....0....2
%e ..0....3....3....0....2....2....3....3....0....3....1....2....0....3....2....0
%e ..2....2....1....3....0....3....4....0....3....0....0....3....3....1....1....1
%e ..1....4....4....4....3....2....1....2....2....4....3....4....1....2....3....3
%K nonn,more
%O 1,4
%A _R. H. Hardin_, Aug 09 2012