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A284435
The number of positive integer sequences of length n with no duplicate substrings (forward or backward) and a minimal product (i.e., the product of the sequence is A282193(n)).
0
1, 1, 2, 2, 4, 4, 4, 48, 144, 144
OFFSET
1,3
EXAMPLE
For n = 7 the a(7) = 4 solutions are:
[1,3,3,2,2,1,1],
[1,2,2,3,3,1,1],
[1,1,3,3,2,2,1], and
[1,1,2,2,3,3,1].
CROSSREFS
Cf. A282193.
Sequence in context: A082849 A211882 A284432 * A156130 A123756 A357256
KEYWORD
nonn,more
AUTHOR
Peter Kagey, Mar 27 2017
STATUS
approved