Yonrenkei (Four-Tile Sequence) - Maximizing Tile Acceptance

What is Yonrenkei?

Yonrenkei (four-tile sequence) is a hand-building term for four consecutive number tiles like “2345m” or “3456p” or “5678s.”

Yonrenkei is two overlapping ryanmen (two-sided) shapes, providing very wide tile acceptance - a highly efficient form.

Basic Forms

Overlapping Structure

2345m breakdown:

【Pattern 1】234 + 345
234m (ryanmen): waits 2/5m
345m (ryanmen): waits 3/6m

【Pattern 2】23 + 34 + 45
23m (ryanmen): waits 1/4m
34m (ryanmen): waits 2/5m
45m (ryanmen): waits 3/6m

Common Usage

Example 1: Recognition

"Have a 2345 yonrenkei"
"Yonrenkei means wide acceptance"

Example 2: Discard choice

"Which to cut from yonrenkei"
"Cut edges, keep good shape"

Example 3: Efficiency talk

"Keep yonrenkei while building"
"Making 234 run from yonrenkei"

Related Terms

• Taatsu: 2-tile meld base
• Ryanmen: In yonrenkei
• Hai-kouritsu: Why yonrenkei is good
• Shuntsu: Made from yonrenkei
• Uke-ire: Yonrenkei’s strength

Common Mistakes

1. Edge tiles

   • 1234, 6789 have lower acceptance
   • Include penchan shape

2. Which to cut

   • Optimal changes with situation
   • Not always cut ends

3. Acceptance calculation

   • Don’t count used tiles
   • Consider visible tiles

4. Shape recognition

   • May not notice yonrenkei
   • Always be aware

Yonrenkei Patterns

Middle Yonrenkei

Widest acceptance:

2345m case:
- Draw 1m: 234m complete, 45m (ryanmen) left
- Draw 3m: 234m complete, 45m (ryanmen) left
- Draw 4m: 345m complete, 23m (ryanmen) left
- Draw 6m: 345m complete, 23m (ryanmen) left

Acceptance: 4 types, 16 tiles (1/3/4/6m × 4 each)

Edge Yonrenkei

1234 case:

- Draw 2m: 123m complete, 34m (ryanmen) left
- Draw 4m: 234m complete, 12m (penchan) left
- Draw 5m: 234m complete, 12m (penchan) left

Acceptance: 3 types, 12 tiles
※12m becomes penchan, less efficient

6789 case:

- Draw 5m: 678m complete, 89m (penchan) left
- Draw 6m: 678m complete, 89m (penchan) left
- Draw 8m: 789m complete, 67m (ryanmen) left

Acceptance: 3 types, 12 tiles
※89m becomes penchan, less efficient

Acceptance Calculation

Ideal Yonrenkei

Live Tile Consideration

2345m with three 1m visible:

Theory: 1/3/4/6m (4 types, 16 tiles)
Actual: 1m(1) + 3/4/6m(4 each) = 13 tiles

→ Still wide even reduced

Discard Selection

Basic Thinking

Hand: 2345m + other tiles

【Choice A】Cut 2m
→ 345m (ryanmen) remains
→ Accepts: 2/5/6m

【Choice B】Cut 5m
→ 234m (ryanmen) remains
→ Accepts: 1/4/5m

【Choice C】Cut 3m
→ 245m (kanchan+penchan)
→ Accepts: 3/6m (inefficient)

Situational Decisions

In Practice

Early Game

• Keep yonrenkei
• Build other melds
• Maintain wide acceptance
• Don’t rush to break

Mid Game

• Fix if near tenpai
• Keep good shape
• Balance with yaku
• Consider value

Late Game

• Fix for win
• Consider safe tiles
• Defense in view

Yonrenkei Value

Efficiency Rating

【High value】
Yonrenkei (4 types, 16 tiles)
  ↓
Ryanmen (2 types, 8 tiles)
  ↓
Kanchan (1 type, 4 tiles)
  ↓
Isolated tile (zero)
【Low value】

Benefits

1. Wide acceptance

   • Up to 16 tiles
   • Quick tenpai

2. High flexibility

   • Any cut keeps good shape
   • Many options

3. Efficient

   • Good tile efficiency
   • Experts value it

Drawbacks

• Hard to add yaku
• May not fit tanyao
• Don’t over-rely

Advanced Use

Double Yonrenkei

Hand: 2345m 3456p

Very strong shape
Extremely wide acceptance
Decide which to fix first

Yonrenkei Development

2345m
  ↓
Draw 3m
  ↓
23345m (run + ryanmen)
  ↓
Cut 2m → 345 + 34 (two good shapes)

Summary

Yonrenkei is four consecutive number tiles - two overlapping ryanmen with excellent efficiency. Middle yonrenkei (2345-5678) has up to 16 tiles acceptance. Beginners should recognize “4 consecutive = yonrenkei” and understand that any discard keeps good shape. Edge yonrenkei (1234, 6789) includes penchan so slightly less efficient, but still valuable. Master yonrenkei for efficient hand building.