145422674

Appears in sequences

• Number of nonempty subsets of {1,2,...,n} in which exactly 1/2 of the elements are <= (n-1)/2.at n=30A047171
• Number of nonempty subsets of {1,2,...,n} in which exactly 1/2 of the elements are <= (n-2)/2.at n=29A047182
• a(n) = binomial(2*n + 2, n + 2) - 1.at n=14A322938