Is there a special symbol for the set: $$ \{1, 2, 3, \dots, n\}$$, or $$\{x| 1\leq x\leq n, n \in \mathbb{Z} \} $$?
$\endgroup$103 Answers
$\begingroup$These are the usual notations (the second is borrowed from computer science): 
Some people use $$\mathbb{N}_k = \{1, 2, \ldots, k\}$$
$\endgroup$1$\begingroup$Consider that for positive reals the standard symbol, as Wikipedia says, is $\mathbb{R}_{>0}$
Then I think that you can use the following symbol for $\{1,2,...,n\}$ $$\mathbb{N}_{\le n}$$
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