We invite you to take place opposite the five performers. As they change position according to specific rules, a seemingly indecipherable movement pattern emerges. Lehmer’s Dance is an intimate, colorful performance that contains subtle rhythms and unpredictable visual changes. While you seek a pattern behind these changes, the anticipated roles of spectator and performer begin to shift.
This performance springs from the collaboration between choreographer Roos van Berkel and mathematician Tom Verhoeff. Verhoeff works on proving a mathematical conjecture by Derrick Henry Lehmer from 1965. It concerns the combinatorics of sequences of colored objects (the performers) that only allow neighbor swaps with the aim to generate all possible sequences (permutations). Applications can be found in cryptology and biochemistry, e.g. to efficiently search through all possible sequences of symbols in a code or biochemical building blocks in a molecule. Restriction to neighbor swaps implies that in each step the sequence changes minimally, thereby maximizing the part that remains the same. This maximizes the amount of work that can be reused from the analysis of the preceding sequence. In many cases it is unavoidable to generate the same sequence more than once, but that should be minimized, to avoid duplicate work. Lehmer formulated a conjecture that Verhoeff proved for two colors and has sharpened further in 2015. The general case is still an open problem. Choreographer Roos van Berkel uses the strict rules that form the basis of the mathematical conjecture in a series of performances.
The performance is a reciprocal, meditative experience that penetrates through outer characteristics and into human contact. ‘Lehmer’s Dance’ uses minimal changes in sequences and movement to reinforce the presence of performer and spectator.
Visitor: ‘The permutations shred prejudice. A blender, not with sharp knives, but with sensitive people that crush me in a trance rhythm.’
Performers: Ayrton Fraenk, Karlijn Roest, Evgenia Rubanova, Denise Verschut, Jurriaan de Vos
Developed with support from Performing Arts Fund NL and Amsterdam Fund for the Arts
Roos van Berkel 