With hundreds of millions of users, spreadsheets are one of the most important end-user
applications. Spreadsheets are easy to use and allow users great flexibility in storing data …

The mandala thangka, as a religious art in Tibetan Buddhism, is an invaluable cultural and
artistic heritage. However, drawing a mandala pattern of thangka style is both time-and effort …

Recognition is considered to be a basic human mental ability in psychology [Myers and
DeWall (2018); Reisberg (2013)]. It consists of identifying the objects (systems, processes …

The non-overlap** sets of pictures are sets such that no two pictures in the set (properly)
overlap. They are the generalization to two dimensions of the cross-bifix-free sets of strings …

We define a set of matrices over a finite alphabet where all possible overlaps between any
two matrices are forbidden. The set is also enumerated by providing some recurrences …

Due to their practicality and convenient parametrization, fractals derived from iterated
function systems (IFSs) constitute powerful tools widely used to model natural and synthetic …

Formal language theory originated in the 1950s as an abstract model of natural language,
which is, of course, a time-ordered sequence, but quite soon attempts were made to apply …

Picture languages generalize classical string languages to two-dimensional arrays. Several
approaches have been proposed during the years; consequently, a general classification …

The notion of unbordered picture generalizes to two dimensions the notion of unbordered
(or bifix-free) string. We extend to two dimensions Nielsen's construction of unbordered …

Pulli kolam is a ubiquitous art form drawn afresh every morning on the threshold of most
homes in South India. It involves drawing a line looped around each dot of a collection of …