Randomized Mission Oak Rocker, #4, Chair, circa 1990Vintage 1990s randomized mission oak rocker by Portland, Oregon Missoula, Montana artist Eric Chesebro. Part of a series of sculptures and prints in which the artist, who is also a mathematician, used the measurements of a vintage mission oak rocking chair and multiplied each measurement by a random number. Chesebro then rebuilt each chair using these new measurements, thereby creating a unique sculpture. This is chair number 4 in a series of 10.