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a(n) is the minimal product of a positive integer sequence of length n with no duplicate substrings of length greater than 1.
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%I #10 Feb 13 2017 20:05:55

%S 1,1,2,2,4,6,12,24,48,120,240,720,1440,4320,8640,25920,60480,181440,

%T 483840,1451520,3870720,11612160,34836480,104509440,348364800,

%U 1045094400,3483648000,10450944000,38320128000,114960384000,459841536000,1379524608000,5518098432000,16554295296000

%N a(n) is the minimal product of a positive integer sequence of length n with no duplicate substrings of length greater than 1.

%C a(n) = sqrt(A282165(n-1)) if A282165(n-1) is square.

%H Peter Kagey, <a href="/A282164/b282164.txt">Table of n, a(n) for n = 1..100</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) = 2 via [1,1,2,1];

%e a(5) = 4 via [1,1,2,2,1];

%e a(6) = 6 via [1,1,2,1,3,1];

%e a(7) = 12 via [1,1,2,2,1,3,1];

%e a(8) = 24 via [1,1,2,1,3,1,4,1];

%e a(9) = 48 via [1,1,2,2,1,3,1,4,1];

%e a(10) = 120 via [1,1,2,1,3,1,4,1,5,1].

%Y Product analog of A259280.

%K nonn

%O 1,3

%A _Peter Kagey_, _Braxton Carrigan_, Feb 07 2017