黒板に書く際の太字に相当します。
| \doubleA | 𝔸 | \doublea | 𝕒 |
| \doubleB | 𝔹 | \doubleb | 𝕓 |
| \doubleC | ℂ | \doublec | 𝕔 |
| \doubleD | 𝔻 | \doubled | 𝕕 |
| \doubleE | 𝔼 | \doublee | 𝕖 |
| \doubleF | 𝔽 | \doublef | 𝕗 |
| \doubleG | 𝔾 | \doubleg | 𝕘 |
| \doubleH | ℍ | \doubleh | 𝕙 |
| \doubleI | 𝕀 | \doublei | 𝕚 |
| \doubleJ | 𝕁 | \doublej | 𝕛 |
| \doubleK | 𝕂 | \doublek | 𝕜 |
| \doubleL | 𝕃 | \doublel | 𝕝 |
| \doubleM | 𝕄 | \doublem | 𝕞 |
| \doubleN | ℕ | \doublen | 𝕟 |
| \doubleO | 𝕆 | \doubleo | 𝕠 |
| \doublep | 𝕡 | \doubleP | ℙ |
| \doubleQ | ℚ | \doubleq | 𝕢 |
| \doubleR | ℝ | \doubler | 𝕣 |
| \doubleS | 𝕊 | \doubles | 𝕤 |
| \doubleT | 𝕋 | \doublet | 𝕥 |
| \doubleU | 𝕌 | \doubleu | 𝕦 |
| \doubleV | 𝕍 | \doublev | 𝕧 |
| \doubleW | 𝕎 | \doublew | 𝕨 |
| \doubleX | 𝕏 | \doublex | 𝕩 |
| \doubleY | 𝕐 | \doubley | 𝕪 |
| \doubleZ | ℤ | \doublez | 𝕫 |
※ \ は、日本語キーボードでは、¥になります。