Bortnyik Sándor, Ritmus 1. 

"Ritmus 1." is a black and white abstract artwork created by Hungarian artist Sandor Bortnyik. The composition is filled with geometric shapes, such as triangles, rectangles, and arcs, arranged in an almost chaotic, yet visually engaging manner. This artwork represents the artist's interest in the principles of rhythm and form, which are central to the principles of abstract art and the art movement known as Constructivism.