2333606218

Appears in sequences

• Number of 2n-bead black-white strings with n black beads and fundamental period 2n.at n=17A007727
• Number of different ways to select n elements from two sets of n elements under the precondition of choosing at least one element from each set.at n=16A115112
• A115112 with initial term changed from 0 to 1.at n=16A171074
• a(n) = binomial(n, [n/2]) - 2.at n=34A201686
• a(n) = Sum_{k=1..n, gcd(n,k) = 1} binomial(n,k)^2.at n=16A337003