155117518

Appears in sequences

• 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=14A115112
• A115112 with initial term changed from 0 to 1.at n=14A171074
• a(n) = binomial(n, [n/2]) - 2.at n=30A201686
• Sum of successive absolute differences of the binomial coefficients = 2*A014495(n).at n=29A218008