Caterer on Beluchenko's p13 is a period-39 oscillator discovered by Jason Summers in January 2009 that is composed of a caterer and a nearby Beluchenko's p13. With a minimum population of 46 cells, it is the smallest known period 39 oscillator, although jam on 34P13 (pictured below) has a smaller bounding box.
Although it is made up of a period-3 oscillator and a period-13 oscillator, it is considered non-trivial because it has a single cell that is alive in generation 11 but dead in the other 38 phases.
Generation 11 reveals the single cell that oscillates at the full period (in green)
- 46P39.1 at Heinrich Koenig's Game of Life Object Catalogs