38488domain: NAppears in sequencesa(n) = 2nd elementary symmetric function of the first n+1 odd positive integers.at n=15A024196Group successively larger composite numbers so that the sum of the n-th group is a multiple of n. Sequence gives the sum of the terms in the n-th group.at n=33A074120(2*7^n - 6*3^n + 4)/6.at n=6A109021