A282167 - OEIS

A282167

a(n) is the minimal sum of a positive integer sequence of length n with no duplicate substrings (forward or backward) of length greater than 1, and no self-adjacent terms.

1, 3, 6, 7, 11, 13, 17, 19, 25, 27

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OFFSET

1,2

COMMENTS

Examples:

[1,1] is invalid because 1 is self-adjacent.

[1,2,3,1,2] is invalid because the substring [1,2] appears twice.

[1,2,1] is invalid because the substring [1,2] appears twice (once forward and once backward).

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

a(1) = 1 via [1];

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

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

a(4) = 7 via [1,2,3,1];

a(5) = 11 via [1,2,3,1,4];

a(6) = 13 via [1,2,3,1,4,2];

a(7) = 17 via [1,2,3,1,4,5,1];

a(8) = 19 via [1,2,3,1,4,2,5,1];

a(9) = 25 via [1,2,3,1,4,2,5,1,6];

a(10) = 27 via [1,2,3,1,4,2,5,1,6,2].

CROSSREFS

Cf. A259280, A282166, A282168.

Sequence in context: A237883 A153033 A353240 * A076644 A214961 A189626

Adjacent sequences: A282164 A282165 A282166 * A282168 A282169 A282170

KEYWORD

nonn,more

AUTHOR

Peter Kagey, Feb 07 2017

STATUS

approved