2097163domain: NAppears in sequencesa(n) = 2^n + ceiling(n/2).at n=21A134522Minimal number (in decimal representation) with n nonprime substrings in base-8 representation (substrings with leading zeros are considered to be nonprime).at n=34A217108a(n) = 2^(2*n - 1) + n.at n=10A221130a(n) = 2^n + 11.at n=21A267615