Persistence: a digit problem

Persistence : A Digit Problem

We examine the persistence of a number, defined as the number of iterations of the function which multiplies the digits of a number until one reaches a single digit number. We give numerical evidence supporting Sloane’s 1973 conjecture that there exists a maximum persistence for every base. In particular, we give evidence that the maximum persistence in each base 2 through 12 is 1, 3, 3, 6, 5, ...

Deconstructing the Digit Recognition Problem

same bias may increase predictive accuracy if it is appropriately applied. Section 4.2 suggests , for example, that a bias toward small trees is relatively more appropriate when attribute errors play an important role in data generation. These details of the factors that determine when cross-validation pruning will increase or decrease predictive accuracy are less crucial for the machine learni...

Can Persistence Hunting Signal Male Quality? A Test Considering Digit Ratio in Endurance Athletes

Various theories have been posed to explain the fitness payoffs of hunting success among hunter-gatherers. 'Having' theories refer to the acquisition of resources, and include the direct provisioning hypothesis. In contrast, 'getting' theories concern the signalling of male resourcefulness and other desirable traits, such as athleticism and intelligence, via hunting prowess. We investigated the...

A Rare Case of Extra Gigantic Digit of Sole

Persistence problem in two-dimensional fluid turbulence.

We present a natural framework for studying the persistence problem in two-dimensional fluid turbulence by using the Okubo-Weiss parameter Λ to distinguish between vortical and extensional regions. We then use a direct numerical simulation of the two-dimensional, incompressible Navier-Stokes equation with Ekman friction to study probability distribution functions (PDFs) of the persistence times...