699999999domain: NAppears in sequencesSmallest number whose sum of digits is 3n.at n=26A133195a(n) = 7*10^n - 1.at n=8A198699a(n+1) is the smallest integer such that the difference between its digital sum and the digital sum of a(n) is n.at n=12A269306Partial sums of A278742.at n=36A280730