It’s surely no coincidence that James Siena’s paintings, drawings and prints have a moiré-ish quality. In this packed, compulsive show, the much-exhibited artist continues to employ what he calls “visual algorithms” to manufacture pattern after abstract pattern, allowing predetermined formal rules to steer the direction and determine the conclusion of any given project. Key to the richness of an approach that on paper might sound rather dry is the element of unpredictability that Siena’s blend of improvisation and repetition maintains. Like Brian Eno’s generative electronic music or the spiraling worlds-within-worlds of fractal geometry, the Californian’s densely composed and tightly rendered works get surprising mileage from simply setting a process in motion and tracing its subsequent branches and mutations. The gallery’s first room is dominated by paintings in glossy enamel on small aluminum panels, unframed and mounted flush to the wall. Some, like Untitled (Small Iterative Grid) and the Peter Halley–esque Two Sequences, are rooted firmly in hard-edged geometry and flat, saturated color. Others, like Sawtoothed Angry Form and Two Scrambled Combs, slide toward the biomorphic. A pair of multipart prints, meanwhile, reveal something of Siena’s sequential construction. In the second room, the artist explores a kind of manic figuration, applying his precise skill with pen and ink, graphite and gouache to the production of works on paper that evoke R. Crumb and Basil Wolverton in their comic-book take on bodily distortion. With this juxtaposition of approaches, Siena keeps us looking and scores another counterintuitive hit.