20167170

Appears in sequences

• Number of nonempty subsets of {1,2,...,n} in which exactly 2/5 of the elements are <= n/3.at n=28A047199
• Number of nonempty subsets of {1,2,...,n} in which exactly 2/5 of the elements are <= (n-1)/3.at n=28A048011
• Number of nonempty subsets of {1,2,...,n} in which exactly 2/5 of the elements are <= (n-2)/3.at n=28A048022