multiplicative digital root

Given an integer m consisting of k digits d1,,dk in base b, let


then repeat this operationMathworldPlanetmath on the digits of j until j<b. This stores in j the multiplicative digital root of m. The number of iterations of the multiplicationPlanetmathPlanetmath operation is called the multiplicative persistence of m.

Title multiplicative digital root
Canonical name MultiplicativeDigitalRoot
Date of creation 2013-03-22 16:00:42
Last modified on 2013-03-22 16:00:42
Owner CompositeFan (12809)
Last modified by CompositeFan (12809)
Numerical id 4
Author CompositeFan (12809)
Entry type Definition
Classification msc 11A63
Synonym repeated digit product
Synonym repeated digital product
Defines multiplicative persistence