Beluchenko's p37 is a period 37 oscillator consisting of 4 loaves and 8 blocks hassling 8 R-pentominoes. It was the first period 37 oscillator to be found, and was discovered by Nicolay Beluchenko on April 14, 2009. It was the only known unique period 37 oscillator until the discovery of 132P37 in March 2010. In terms of its 124 cells, it currently smallest known period 37 oscillator. Adam P. Goucher noticed that two of these oscillators could interact non-trivially by hassling a beehive and a block.
Two copies of 124P37 hassling a beehive and a blockDownload RLE: click here