Find all integers n such that S(n) = S(2n) = ... = S(n*n), where S is the sum of the base-10 digits. See Jeff Erickson's solution. © Copyright 1996 Stan Wagon. Reproduced with permission.

Find all integers n such that S(n) = S(2n) = ... = S(n*n), where S is the sum of the base-10 digits.

© Copyright 1996 Stan Wagon. Reproduced with permission.