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A118771
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Let a "sum" be a set {x,y,z} of distinct natural numbers such that x+y=z and let N_m={1,2,...m}. a(n) is the smallest s such that there is no partition of N_s into n sum-free parts.
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3
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OFFSET
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1,1
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COMMENTS
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a(5) >= 190 (see Blanchard et al. at p. 7). - Michel Marcus, Mar 26 2013
a(5) >= 197, a(6) >= 583, a(7) >= 1741, a(8) >= 5202, a(9) >= 15597 (see Ahmed et al. at p. 3). - Stefano Spezia, Aug 25 2023
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LINKS
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EXAMPLE
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For n=1, a(1)=3 as there is no partition of N_3={1,2,3} into 1-sum-free parts. In the same way a(2)=9...
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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R. Reis (rvr(AT)ncc.up.pt), May 22 2006
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STATUS
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approved
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