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|gameExample = [http://tenhou.net/0/?log=2013122121gm-0089-0000-x9faca343bf4e&tw=2 Using riichi]
|gameExample = [http://tenhou.net/0/?log=2013122121gm-0089-0000-x9faca343bf4e&tw=2 Using riichi]
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'''Ryanmen''' {{kana|両面}} is the most commonly occurring [[machi|wait pattern]] in the game. Commonly referred as the "open wait", this pattern involves two consecutively numbered tiles, waiting on the "outside" number. For example, a 3-4 needs either a 2 or a 5 in order to form [[Mentsu|tile groups]] of either 2-3-4 or 3-4-5. By far, this is the most efficient wait pattern, as it uses just two tiles while waiting on a maximum of eight possible tiles.
'''Ryanmen''' {{kana|両面}}, often referred as an "open wait", is the most common [[machi|wait pattern]] in the game. It involves two consecutively numbered tiles, waiting on either "outside" number. For example, a 3-4 needs either a 2 or a 5 in order to form a [[sequence]] of either 2-3-4 or 3-4-5. A ryanmen cannot be formed with [[terminal]] tiles. It is, by far, the most efficient wait pattern: it waits for 8 tiles (of two types) while only using 2 tiles.


==Pattern==
==Pattern==
{{#mjt:000000z45s00000z}} Waiting for: {{#mjt:3s}} or {{#mjt:6s}}
{{#mjt:000000z45s00000z}} Waiting for: {{#mjt:3s}} or {{#mjt:6s}}


Ryanmen always waits for two tiles. In addition, two ryanmen patterns may combine to form a [[ryanmenten]], which waits for 3 tiles instead of two.
Ryanmen always waits for two tiles.  
 
===Sanmenchan===
{{#mjt:000000z45678s00000z}} Waiting for: {{#mjt:3s}}, {{#mjt:6s}}, {{#mjt:9s}}
 
When a ryanmen is adjacent to a complete sequence, forming 5 consecutive number tiles, it forms a [[sanmenchan]] - which waits for 3 tiles instead of 2. This is because the hand can be interpreted in one of two ways:
 
*{{#mjt:45s}} ryanmen + {{#mjt:678s}} sequence;  Waiting for: {{#mjt:3s}}, {{#mjt:6s}}
 
*{{#mjt:456s}} sequence + {{#mjt:78s}} ryanmen;  Waiting for: {{#mjt:6s}}, {{#mjt:9s}}


==Fu==
==Fu==
Due to its relatively ease, the ryanmen pattern is not awarded any fu. The inability to gain fu based on ryanmen makes it an essential component to the yaku, [[pinfu]]. The yaku, [[pinfu]], requires ryanmen, because the waiting pattern does not produce fu.  [[Ryanmenten]] is also allowed, as nested ryanmen do not produce fu either.
Due to its relative ease, a ryanmen wait is not awarded any fu.
 
As it lacks fu, a ryanmen wait is required for [[pinfu]]. To score pinfu, you must have a ryanmen (or a [[complex waits|complex wait]] which can be interpreted as ryanmen), as all other waiting patterns end up scoring fu.


==Usage==
==Usage==
Ryanmen is the most common wait pattern, due to both convenience and probability.
Ryanmen is the most frequently used wait in the game, due to its strength and probability. Approximately 50% of all hands, and 66% of all [[riichi]] hands, use a ryanmen wait.
*It is the most powerful of the basic waits. A ryanmen waits for a maximum of 8 tiles of two different types. All other basic wait patterns can wait for a maximum of 4 tiles - ryanmen is twice as big.
*Unlike [[complex waits]], ryanmen only requires two tiles to form, thus making ryanmen much more likely to form than a complex wait.
*[[Pinfu]], a common [[yaku]], requires a ryanmen or ryanmen-derived wait.
 
Whether a hand is in [[tenpai]] or not, ryanmen waits are efficient to use.


===Suji===
===Suji===
Line 25: Line 41:
{{main|Suji}}
{{main|Suji}}


Ryanmen is directly related to [[suji]], or the '''mahjong intervals'''. At any time, ryanmen waits on a pair based on the three intervals of: 1-4-7, 2-5-8, and 3-6-9. 
[[Suji]] (i.e. "mahjong intervals") is a [[defensive]] concept directly related to ryanmen waits. In essence, when a tile is suji, it would be impossible for an opponent to have a ryanmen wait without being in [[furiten]].
 
:{{#mjt:000000z23p00000z}} Waiting for: {{#mjt:1p}} or {{#mjt:4p}}
 
In this example, the consecutive 2-3 needs either of the two waiting tiles in order to complete the sequence.  The 1 and 4 is included in the 1-4-7 interval.


===Frequency===
* A ryanmen will always wait on tiles that are three apart, forming the intervals: 1-4-7, 2-5-8, and 3-6-9. For example, a 2-3 ryanmen waits for either a 1 or 4, and is thus part of the 1-4-7 interval.
Due to the ease of use, ryanmen waits are by far the most commonly used wait pattern.  Its biggest advantage stems on the maximum 8-tile count on two tile types.  This is assuming both types are live tiles. In addition, the yaku pinfu requires ryanmen. making it one of the more frequently used yaku. As a two-tile pattern to complete a sequence, it is also a very compact shape leaving plenty of room to develop numerous hand patterns with the rest of the hand. In other words, it is a very efficient waiting pattern to use. This concept is applicable whether the hand is tenpai or not.
* Therefore, if an opponent discards a 4, they cannot have a ryanmen wait on a 1 or 7 of the same suit (without being in [[furiten]], which would prevent them from winning off ''your'' discarded tile). So after an opponent discards a 4, it is safer to discard a 1 or 7.
* If the opponent discards a 1, then the 4 is not necessarily safe: they could still have a 4-7 ryanmen wait. For 4 to be "full" suji, both 1 and 7 must be discarded.


==External links==
==External links==

Revision as of 21:58, 12 June 2024

Ryanmen
Kanji 両面
English Open wait
Fu 0 fu
Tile types waiting 2 sided wait
Tiles available 8 tiles
Pattern example
Tenhou.net example Using riichi

Ryanmen 「両面」, often referred as an "open wait", is the most common wait pattern in the game. It involves two consecutively numbered tiles, waiting on either "outside" number. For example, a 3-4 needs either a 2 or a 5 in order to form a sequence of either 2-3-4 or 3-4-5. A ryanmen cannot be formed with terminal tiles. It is, by far, the most efficient wait pattern: it waits for 8 tiles (of two types) while only using 2 tiles.

Pattern

Waiting for: or

Ryanmen always waits for two tiles.

Sanmenchan

Waiting for: , ,

When a ryanmen is adjacent to a complete sequence, forming 5 consecutive number tiles, it forms a sanmenchan - which waits for 3 tiles instead of 2. This is because the hand can be interpreted in one of two ways:

  • ryanmen + sequence; Waiting for: ,
  • sequence + ryanmen; Waiting for: ,

Fu

Due to its relative ease, a ryanmen wait is not awarded any fu.

As it lacks fu, a ryanmen wait is required for pinfu. To score pinfu, you must have a ryanmen (or a complex wait which can be interpreted as ryanmen), as all other waiting patterns end up scoring fu.

Usage

Ryanmen is the most frequently used wait in the game, due to its strength and probability. Approximately 50% of all hands, and 66% of all riichi hands, use a ryanmen wait.

  • It is the most powerful of the basic waits. A ryanmen waits for a maximum of 8 tiles of two different types. All other basic wait patterns can wait for a maximum of 4 tiles - ryanmen is twice as big.
  • Unlike complex waits, ryanmen only requires two tiles to form, thus making ryanmen much more likely to form than a complex wait.
  • Pinfu, a common yaku, requires a ryanmen or ryanmen-derived wait.

Whether a hand is in tenpai or not, ryanmen waits are efficient to use.

Suji

Suji (i.e. "mahjong intervals") is a defensive concept directly related to ryanmen waits. In essence, when a tile is suji, it would be impossible for an opponent to have a ryanmen wait without being in furiten.

  • A ryanmen will always wait on tiles that are three apart, forming the intervals: 1-4-7, 2-5-8, and 3-6-9. For example, a 2-3 ryanmen waits for either a 1 or 4, and is thus part of the 1-4-7 interval.
  • Therefore, if an opponent discards a 4, they cannot have a ryanmen wait on a 1 or 7 of the same suit (without being in furiten, which would prevent them from winning off your discarded tile). So after an opponent discards a 4, it is safer to discard a 1 or 7.
  • If the opponent discards a 1, then the 4 is not necessarily safe: they could still have a 4-7 ryanmen wait. For 4 to be "full" suji, both 1 and 7 must be discarded.

External links