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%I #17 Sep 26 2019 08:10:33
%S 1,1,2,4,6,12,36,96,240,480,1440,5760
%N a(n) is the minimal product of a positive integer sequence of length n with no duplicate substrings (forward or backward) of length greater than 1.
%H Peter Kagey, <a href="/A282193/a282193_1.hs.txt">Haskell program for A282193</a>.
%e a(1) = 1 via [1];
%e a(2) = 1 via [1,1];
%e a(3) = 2 via [1,1,2];
%e a(4) = 4 via [1,1,2,2];
%e a(5) = 6 via [1,1,2,3,1];
%e a(6) = 12 via [1,1,2,2,3,1];
%e a(7) = 36 via [1,1,2,2,3,3,1];
%e a(8) = 96 via [1,1,2,2,3,1,4,2];
%e a(9) = 240 via [1,1,2,2,3,1,4,5,1];
%e a(10) = 480 via [1,1,2,2,3,1,4,2,5,1];
%e a(11) = 1440 via [1,1,2,2,3,3,1,4,2,5,1];
%e a(12) = 5760 via [1,1,2,2,3,1,4,2,5,1,6,2].
%e ...
%e [1,2,3,1,2] is invalid because the substring [1,2] appears twice.
%e [1,2,1] is invalid because the substring [1,2] appears twice (once forward and once backward).
%Y Cf. A282168 is the sum analog.
%Y Cf. A282164, A282169, A282170.
%K nonn,more
%O 1,3
%A _Peter Kagey_, Feb 08 2017
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