Difference between revisions of "B-heptomino"
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|name = B-heptomino | |name = B-heptomino | ||
|pname = bheptomino | |pname = bheptomino | ||
|c = 7 | |c = 7 | ||
|bx = 4 | |bx = 4 | ||
|by = 3 | |by = 3 | ||
|l = 148 | |||
|f = 28 | |||
|mcps = 7 | |||
|discoverer = John Conway | |discoverer = John Conway | ||
|discoveryear = 1970 | |discoveryear = 1970 | ||
|synthesis = 2 | |synthesis = 2 | ||
|synthesisRLE = true | |synthesisRLE = true | ||
|plaintext = true | |plaintext = true | ||
|rle = true | |rle = true | ||
}} | }} | ||
The '''B-heptomino''' is a very common [[methuselah]] that evolves into three [[block]]s, two [[glider]]s and a [[ship]] after 148 generations. Compare with [[Herschel]], which appears at generation 20 of B-heptomino's evolution. | The '''B-heptomino''' (or B-heptaplet, if the top-left cell is shifted one cell left) is a very common [[methuselah]] that evolves into three [[block]]s, two [[glider]]s and a [[ship]] after 148 generations. Compare with [[Herschel]], which appears at generation 20 of the B-heptomino's evolution. B-heptominoes acquired particular importance in {{year|1996}} due to [[David Buckingham]]'s work on [[B track]]s. | ||
This pattern often arises with the cell at top left shifted one space to the left, producing a seven-bit [[polyplet]] that shares the same eight-bit descendant but is not technically a heptomino at all. Many conduits produce this form of B via the R-pentomino, so these two forms of B can be used interchangeably when marking in conduits. | |||
The B-heptomino is considered a failed [[puffer]] or failed [[spaceship]], since on its own it travels at c/2 for only a short time before being affected by its own trailing debris. However, it can be stabilized into a c/2 puffer or into a [[clean]] c/2 rake or spaceship. See, e.g., [[puffer 2]], [[backrake 2]], [[ecologist]], or [[pufferfish]]. | |||
== In other rules == | |||
The B-heptomino is a stable puffer, spaceship, replicator, or oscillator in many [[Isotropic non-totalistic Life-like cellular automaton | non-totalistic]] rules. | |||
For example: | |||
* In B3/S23-e4e, it evolves into a (16,5)c/74 [[oblique spaceship]]. | |||
* In B3/S23-a, it is a glide-symmetric 10c/20 spaceship. | |||
* In B34ej5y6n/S23, it is an oblique [[Infinite growth#Quadratic|quadratic]] [[replicator]], one of only a few known. | |||
* In B36n/S2-i36c7c, it evolves into a glide-symmetric 9c/70 diagonal spaceship. | |||
==Image gallery== | ==Image gallery== | ||
<gallery> | <gallery> | ||
Image:BheptominoGen20.png|Generation 20 of the B-heptomino | Image:BheptominoGen20.png|Generation 20 of the B-heptomino, showing its [[Herschel]] offspring | ||
Image:BheptominoFinal.png|Generation 148 of the B-heptomino | Image:BheptominoFinal.png|Generation 148 of the B-heptomino | ||
Image:Bparent. | Image:Bparent.png|A 6-cell parent of the B-heptomino | ||
</gallery> | </gallery> | ||
==See also== | ==See also== | ||
*[[Herschel]] | |||
*[[C-heptomino]] | *[[C-heptomino]] | ||
*[[Conduit 1]] | *[[Conduit 1]] |
Revision as of 12:15, 26 April 2020
B-heptomino | |||||||
View static image | |||||||
Pattern type | Methuselah | ||||||
---|---|---|---|---|---|---|---|
Number of cells | 7 | ||||||
Bounding box | 4 × 3 | ||||||
MCPS | 7 | ||||||
Lifespan | 148 generations | ||||||
Final population | 28 | ||||||
L/I | 21.1 | ||||||
F/I | 4 | ||||||
F/L | 0.189 | ||||||
L/MCPS | 21.1 | ||||||
Discovered by | John Conway | ||||||
Year of discovery | 1970 | ||||||
| |||||||
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The B-heptomino (or B-heptaplet, if the top-left cell is shifted one cell left) is a very common methuselah that evolves into three blocks, two gliders and a ship after 148 generations. Compare with Herschel, which appears at generation 20 of the B-heptomino's evolution. B-heptominoes acquired particular importance in 1996 due to David Buckingham's work on B tracks.
This pattern often arises with the cell at top left shifted one space to the left, producing a seven-bit polyplet that shares the same eight-bit descendant but is not technically a heptomino at all. Many conduits produce this form of B via the R-pentomino, so these two forms of B can be used interchangeably when marking in conduits.
The B-heptomino is considered a failed puffer or failed spaceship, since on its own it travels at c/2 for only a short time before being affected by its own trailing debris. However, it can be stabilized into a c/2 puffer or into a clean c/2 rake or spaceship. See, e.g., puffer 2, backrake 2, ecologist, or pufferfish.
In other rules
The B-heptomino is a stable puffer, spaceship, replicator, or oscillator in many non-totalistic rules. For example:
- In B3/S23-e4e, it evolves into a (16,5)c/74 oblique spaceship.
- In B3/S23-a, it is a glide-symmetric 10c/20 spaceship.
- In B34ej5y6n/S23, it is an oblique quadratic replicator, one of only a few known.
- In B36n/S2-i36c7c, it evolves into a glide-symmetric 9c/70 diagonal spaceship.
Image gallery
Generation 20 of the B-heptomino, showing its Herschel offspring
See also
External links
- B-heptomino at the Life Lexicon