# OCA Discovery of the Year

This article is a stub. You can help LifeWiki by expanding it. |

The **OCA Discovery of the Year**^{[note 1]} (**OCADOTY**) competition is held each year on the ConwayLife.com forums as a counterpart to Pattern of the Year dedicated to rules other than Conway's Game of Life. Users are invited to submit interesting and noteworthy patterns, rules, families of rules, or projects relating to other cellular automata, their own or others'; following discussion, a final list is then curated, and a public vote held. All entries must have been found during the year in question.

## Results by year

### 2020

The 2020 OCA Discovery of the Year competition is currently taking place, and is being organized by Peter Naszvadi.

### 2019

The OCA Discovery of the Year competition for 2019 was organized by testitemqlstudop and bubblegum.

Final rank | Stars | Pattern | Author | Link(s) |
---|---|---|---|---|

Description | ||||

=1 | 37 | Dominoplex Orthogonoid | 2718281828 | [1] |

Orthogonoid spaceship in rule B2cen3ek4ejkwz5-ein6an7e8/S12an3-eijq4enrty5e6k. | ||||

=1 | 37 | Orthogonoid | AforAmpere | [2] |

Speed orthogonoid spaceship in rule B2ein3cijn4cnrwy5cnq6e/S1c2-ai3acny4anqy5c6ek8. | ||||

3 | 33 | Snowflakes' pseudo-Orthogonoid | Goldtiger997 et al. (2718281828, dani, toroidalet, BlinkerSpawn etc.) | [3] |

A pseudo-orthogonoid, a self-constructing puffer. | ||||

4 | 26 | RROs | 2718281828 and AforAmpere | [4] |

massive reflectorless rotating oscillators. | ||||

5 | 25 | 3S1CShip8 and its c/2^6911+6913 one-cell ship | fluffykitty | [5] |

3S1CShip8 and its c/2^6911+6913 one-cell ship. | ||||

6 | 24 | Non-explosive B1e rules | toroidalet, Saka, testitemqlstudop, wildmyron, A for awesome et al | [6] |

Non-explosive B1e rules. | ||||

7 | 23 | B2a/S circuitry | toroidalet | [7] |

Signal logic circuitry with replicator streams | ||||

8 | 22 | Additions to the 5S project | wildmyron et al | [8] |

Additions to the 5S project, especially these ones: (176,1)c/440, 108c/37886 diagonal, (98,97)c/4312 | ||||

9 | 21 | GUYTU6J's OCA discoveries | GUYTU6J | [9] [10] [11] [12] |

Triangular and ruler replicator + SMOS, 2D replicator with beautiful fractal, 2D replicator firing gliders and 10c/20s, Bizarre rake-plicator | ||||

10 | 20 | Hactar's 2x2 p2 metacells | HactarCE | [13] |

Hactar's 2x2 p2 metacells simulating outer-totalistic life-like rules. | ||||

11 | 18 | Omosso's pair-interaction ships | 77topaz et al | [14] |

Omosso's pair-interaction ships with very high periods. | ||||

=12 | 17 | Mahler-rep | Letters | [15] |

Mahler-rep, a modification of Devore which allows for smaller replicators and computers. | ||||

=12 | 17 | Rule X3VI | Rhombic, testitemqlstudop et al | [16] |

The first INT rule to reach 1T objects in C1 on Catagolue. | ||||

14 | 16 | W110 in Codd | Naszvadi | [17] [18] |

Usual W110 Unit cell that proves Turing-completeness of a classic 8-state vN rule by E.F. Codd. | ||||

15 | 15 | ZombieLife | 77topaz, Moosey, dani, dvgrn et al | [19] |

A rule with its enormous natural spaceships. |

### 2018

The nominations for the 2018 competition were organized by Rhombic, and the voting by 77topaz. Users were able to vote on as many entries as they wished, awarding up to three stars to each one.

Final rank | Stars | Pattern | Author | Link(s) |
---|---|---|---|---|

Description | ||||

1 | 38 | Adjustable slope spaceships | AforAmpere | [20] |

Spaceships which can be adjustable to travel at any integer slope. | ||||

2 | 24 | bf esolang simulator | M.I. Wright | [21] |

A cellular automaton simulating the bf programming language. | ||||

=3 | 23 | ATPP | dani | [22] |

A rule containing many spaceships based on failed replicators as well as several actual replicators based on it. | ||||

=3 | 23 | Exponentially long-lasting methuselahs | toroidalet | [23] |

Various fuse-based methuselahs, one of which has an estimated lifespan of 2^{2^50} generations.
| ||||

5 | 22 | Smallest Oscillators Supporting Specific Periods | Oscar Cunningham | [24] |

Examples of two-cell oscillators for every period up to 102. | ||||

6 | 21 | 8c/9 orthogonal spaceship | AforAmpere | [25] |

The fastest known sub-lightspeed spaceship in an isotropic non-totalistic rule without B0. | ||||

7 | 20 | Suns | Goldtiger997 | [26] |

A rule containing a high-period oscillator which can be hassled at various other periods. | ||||

8 | 18 | JvN29 loop-based replicator | fluffykitty, Redstoneboi | [27] |

A replicator in von Neumann's original cellular automaton. | ||||

=9 | 17 | Omosso | Saka | [28] |

A rule containing high-period spaceships, a natural RRO, and OMOSes of various periods, hence its name. | ||||

=9 | 17 | Rule 110 unit cells in various rules | Peter Naszvadi, Luka Okanishi, LaundryPizza03 | [29] [30] [31] [32] |

Proofs of Turing-completeness for rules including but not limited to HighLife, DryLife, and LowDeath. | ||||

11 | 16 | tlife puffer | dani, Luka Okanishi | [33] [34] |

An 8c/282 orthogonal puffer, and a spaceship based on it. | ||||

=12 | 15 | Hype | FlameandFury | [35] |

A rule with a wide variety of high-period oscillators which has also been proven omniperiodic. | ||||

=12 | 15 | Hive | dani | [36] |

A rule with a failed replicator from which various high-period and unusual-speed spaceships have been constructed. | ||||

=14 | 14 | Record-slowest spaceships | AforAmpere | [37] |

A rule table supporting spaceships based on Knuth's up-arrow notation, allowing for unimaginably slow speeds. | ||||

=14 | 14 | Emitters | dani | [38] |

A rule with many high-period oscillators (similar to Hype) but also a small spacefiller, a replicator, and several guns. | ||||

16 | 13 | Other adjustable spaceships | Luka Okanishi, muzik, Arie Paap, 2718281828, AforAmpere | [39] |

17 | 11 | Other RROs | 2718281828, et al. | [40] |

18 | 10 | Arrow | 77topaz | [41] |

A rule with adjustable rakes and many known reactions based on them. |

### 2017

The 2017 competition was organized by Rhombic. Users were able to vote on as many entries as they wished, awarding up to three stars to each one.

Final rank | Stars | Pattern | Author | Link(s) |
---|---|---|---|---|

Description | ||||

1 | 25 | Orthogonal adjustable spaceships | Aidan F. Pierce, Luka Okanishi | [42] [43] |

Two rules allowing for the trivial construction of infinitely many odd and even-period spaceships respectively. | ||||

2 | 18 | 5s project | dani, et al. | [44] |

A collection of the smallest known spaceships of every speed among the isotropic non-totalistic rulespace. | ||||

=3 | 15 | SMOSMOS | Saka, et al. | [45] |

The first known spaceships made of SMOSes, with various examples posted. | ||||

=3 | 15 | Movostill 3 | dani | [46] |

A rule with various elementary spaceships and guns as well as construction potential. | ||||

=3 | 15 | HighLife replicator spaceships | Luka Okanishi | [47] [48] [49] |

Replicator-based spaceships traveling at speeds of c/18, c/12, and c/30 diagonal respectively. | ||||

=6 | 14 | tDryLife pondlayer-based spaceship | Luka Okanishi | [50] |

An engineered spaceship based on a high-period pond puffer. | ||||

=6 | 14 | One-cell universal constructor | blah | [51] |

A method of producing arbitrary complex patterns from a single cell using rule tables. | ||||

8 | 12 | Snowflakes | Blinkerspawn, dani | [52] |

A rule with construction potential despite its differences from Conway's Game of Life. | ||||

9 | 11 | Rule 110 unit cells in various rules | Peter Naszvadi | [53] [54] [55] [56] |

Proofs of Turing-completeness for certain Life-like rules including but not limited to Pedestrian Life, EightLife, and HoneyLife. | ||||

=10 | 9 | Spaceship-bouncing-off-object adjustable spaceships | muzik | [57] |

=10 | 9 | Extremely slow spaceships | Blinkerspawn, et al. | [58] |

The design of spaceships with excruciatingly slow speeds using different approaches | ||||

12 | 7 | Slope 73 spaceship | AforAmpere | [59] |

A (73,1)c/160 spaceship, at the time the oblique spaceship with the steepest known slope. | ||||

13 | 6 | Larger than Life developments | Saka, muzik, et al. | [60] [61] [62] |

A collective entry for various discoveries within the Larger than Life rulespace. |

## Notes

- ↑ "OCA" is an acronym for "other cellular automata."