8023886domain: NAppears in sequencesa(0) = 1, a(1) = 2; for n>=2 a(n) is the number of degree-n reducible polynomials over GF(2).at n=23A058766Number of integers in {1, 2, ..., 2^n} that are coprime to n.at n=22A0749332^(n-1) - floor((2^(n-1) - 1)/(n-1)).at n=22A213255