Basic Solution
To create a set of n
elements, pass a list or another iterable of n
initial elements into the set()
function. For example, set(range(n))
creates the set of n
consecutive integers {1, 2, ..., n-1}
. You can then add and remove the elements using the normal set methods such as add()
or pop()
.
Here’s an example:
n = 100 my_set = set(range(n)) print(my_set) ''' The output is: {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99} '''

Set Comprehension
To create a set of size n
by modifying an existing iterable of elements, you can use the set comprehension feature in Python. For example, {x*x for x in range(n)}
creates the set of n square numbers in a single line of code.
Here’s the full code example:
n = 100 squared = {x*x for x in range(n)} print(squared) ''' The output is: {0, 1, 1024, 4096, 4, 9216, 9, 16, 529, 3600, 4624, 25, 36, 2601, 49, 7225, 3136, 64, 576, 1089, 1600, 2116, 5184, 6724, 7744, 9801, 81, 8281, 6241, 100, 625, 121, 4225, 1156, 8836, 3721, 144, 1681, 2704, 5776, 4761, 2209, 676, 169, 3249, 9409, 196, 1225, 5329, 729, 225, 1764, 7396, 6889, 7921, 2809, 256, 2304, 6400, 3844, 4356, 784, 1296, 8464, 289, 3364, 4900, 5929, 1849, 9025, 324, 841, 1369, 2401, 2916, 5476, 361, 3969, 900, 9604, 4489, 400, 1936, 7056, 7569, 3481, 6561, 1444, 8100, 5041, 441, 961, 2500, 6084, 8649, 3025, 484, 2025, 1521, 5625} '''
Feel free to watch my explainer video on set comprehension and have a look at the full guide on the Finxter blog too!
π Recommended Tutorial: Python Set Comprehension Full Guide
Related – Creating a Python List of Size n
If you want to create a set of size n
, another idea that works in some cases is to create a list of size n
and then convert the list to a set. However, be aware of the fact that sets do not contain duplicates so a list of size n
could easily become a set of size 1
if all elements in the list are duplicates!
Here’s how you can create a list of size n:
π Recommended Tutorial: How to Create a Python List of Size n?

While working as a researcher in distributed systems, Dr. Christian Mayer found his love for teaching computer science students.
To help students reach higher levels of Python success, he founded the programming education website Finxter.com that has taught exponential skills to millions of coders worldwide. He’s the author of the best-selling programming books Python One-Liners (NoStarch 2020), The Art of Clean Code (NoStarch 2022), and The Book of Dash (NoStarch 2022). Chris also coauthored the Coffee Break Python series of self-published books. He’s a computer science enthusiast, freelancer, and owner of one of the top 10 largest Python blogs worldwide.
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