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%I #5 Mar 28 2017 15:02:57
%S 1,1,2,2,4,4,4,48,48,144
%N The number of positive integer sequences of length n with no duplicate substrings (forward or backward) and a minimal sum (i.e., the sum of the sequence is A282168(n)).
%e For n = 7 the a(7) = 4 solutions are:
%e [1,3,3,2,2,1,1],
%e [1,2,2,3,3,1,1],
%e [1,1,3,3,2,2,1], and
%e [1,1,2,2,3,3,1].
%Y Cf. A282168.
%K nonn,more
%O 1,3
%A _Peter Kagey_, Mar 27 2017