203489

Appears in sequences

• Number of nonempty subsets of {1,2,...,n} in which exactly 1/2 of the elements are <= (n-4)/2.at n=20A048060
• Number of nonempty subsets of {1,2,...,n} in which exactly 1/2 of the elements are <= (n+3)/3.at n=20A048082
• a(n) = binomial(n+8,8) - 1.at n=13A165618
• a(n) = number of nonempty subsets S of {1,2,...,n} such that (number of nonprimes in S) = (number of primes in S).at n=21A369854