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A338006
Maximal size of a subset of {1..n} such that every pair of (not necessarily distinct) elements has a different product.
2
1, 2, 3, 3, 4, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 13, 13, 13, 14, 14, 15, 15, 15, 16, 17, 17, 18, 18, 19, 19, 19, 19, 20, 20, 20, 21, 22, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26, 27, 27, 28, 28, 29, 29, 30, 30, 31, 31, 31, 31, 31, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 36, 36, 36, 37, 37, 37, 37, 38
OFFSET
1,2
FORMULA
a(n) = max {k >= 1; A347498(k) <= n}. - Pontus von Brömssen, Sep 09 2021
CROSSREFS
Sequence in context: A006161 A132351 A025556 * A005229 A091245 A347649
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(52)-a(83) from Bert Dobbelaere, Oct 18 2020
STATUS
approved