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A348481
a(n) is the number of n-element subsets of {1,2,3,...,A347498(n)} with the property that all products i * j are distinct for i <= j.
0
1, 1, 1, 3, 1, 1, 1, 5, 15, 6, 12, 45, 2, 65, 4, 4, 4, 44, 2, 392
OFFSET
1,4
EXAMPLE
For n = 8, A347498(n) = 11, and the a(8) = 5 8-element subsets of {1,2,...,11} with distinct pairwise products are
{1,2,5,6,7,8,9,11};
{1,2,6,7,8,9,10,11};
{1,5,6,7,8,9,10,11};
{2,3,5,7,8,9,10,11}; and
{2,5,6,7,8,9,10,11}.
CROSSREFS
Sequence in context: A300853 A293012 A341033 * A274391 A368862 A339768
KEYWORD
nonn,more
AUTHOR
Peter Kagey, Oct 20 2021
EXTENSIONS
a(18)-a(20) from Michael S. Branicky, Oct 28 2021
STATUS
approved