What is the type of letter $\mathbb {A,B,C,D,...}$ called

Question

$\mathbb {N,P,Q,R,Z}$ all represent commonly used sets of numbers, but I can't find any good references on what they're called. I've tried double bar, double stroke, and googling what the ____ number symbol was called; inserting for integers, primes, etc.

What is it called?

Some people prefer to use plain bold, e.g., $\textbf Z$ rather than $\mathbb Z$. — Robert Soupe, Jun 13 '17 at 23:59
I'd argue that this post is on topic (and you should vote to reopen if you have the rep), because mathematical writing is part of mathematics. — , Jun 14 '17 at 05:10

score 4 · Accepted Answer · answered Jun 12 '17 at 01:27

4

My answer isn't authoritative, but I've always heard them called "blackboard" or "blackboard bold" letters. Note that the TeX command is \mathbb, where the "bb" stands for "blackboard."

answered Jun 12 '17 at 01:27

What is the type of letter $\mathbb {A,B,C,D,...}$ called

1 Answers1