Clock was found by Simon Norton in May 1970. It serves as the logo pattern for WinLifeSearch.
Extensions of the oscillator can be seen as stabilisations for the zebra stripes/chicken wire agar - such extensions lose symmetry.
Clock is the sixth most common oscillator in Achim Flammenkamp's census, being somewhat less frequent than the pentadecathlon, but much rarer than the blinker, toad, beacon or pulsar. It is surprisingly rare considering its small size. It is also the sixty-second most common object on Adam P. Goucher's Catagolue.
In other rules
In outer-totalistic rules, clock can follow at least three different p2 cycles depending on the rule, which all have mod 1.
- In rules such as B4/S1 the inner two cells oscillate similarly to a duoplet in Seeds.
- In rules such as B3/S3, the outer cells oscillate (this being the sequence seen in Life).
- In rules such as B34/S, both of these evolutions take place simultaneously, causing it to evolve into an inverted version of itself and therefore making it a phoenix.
Further sequences are possible in non-totalistic rules; for instance, in B3j/S1, clock cycles with one phase of toad. This gives at least four different p2 sequences:
Evolution of the clock across different rules
|B3/S3 to B35678/S02345678
||B34/S to B345678/S0245678
|B4/S1 to B45678/S01245678
||B3j/S1 to B2cin3-nq4-j5678/S012-k3-y45678
- 6P2.3 at Heinrich Koenig's Game of Life Object Catalogs