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A288728 Number of sum-free sets that can be created by adding n to all sum-free sets [1..n-1]. 0
1, 1, 3, 3, 7, 8, 18, 19, 47, 43, 102, 116, 238, 240, 553, 554, 1185, 1259, 2578, 2607, 5873, 5526, 11834, 12601, 24692, 24390, 53735, 52534, 107445, 107330, 218727, 215607, 461367, 427778, 891039, 910294, 1804606, 1706828, 3695418, 3411513, 7136850, 6892950 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Using the standard definition of sum-free set, this is simply the difference of successive terms in A007865.

LINKS

Table of n, a(n) for n=1..42.

Eric Weisstein's World of Mathematics, Sum-Free Set

FORMULA

a(n) = A007865(n) - A007865(n-1).

EXAMPLE

1 can be added to {};

2 can be added to {} but not {1};

3 can be added to {},{1},{2};

4 can be added to {},{1},{3} but not {2},{1,3},{2,3}.

CROSSREFS

Cf. A007865.

Sequence in context: A286110 A116157 A056357 * A213942 A144554 A177936

Adjacent sequences:  A288725 A288726 A288727 * A288729 A288730 A288731

KEYWORD

nonn

AUTHOR

Ben Burns, Jun 14 2017

STATUS

approved

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Last modified March 19 11:10 EDT 2019. Contains 321329 sequences. (Running on oeis4.)