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Python Coding Challenges

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467 challenges 330 easy 120 medium 17 hard
Math & Number Theory easy

Nth Triangular Number

Implement a function that returns the nth triangular number efficiently.

math formula integers
1
+10 pts 10m
Math & Number Theory easy

Integer Square Root Floor

Implement a function that returns the greatest integer whose square is ≤ n, using only integer operations.

math binary-search integer
+8 pts 12m
Math & Number Theory easy

Euler Totient Function

Implement Euler's totient function φ(n) for positive integers.

math number-theory totient
+10 pts 15m
Math & Number Theory easy

Sieve of Eratosthenes

Implement the Sieve of Eratosthenes to return a sorted list of all primes up to a given integer n.

primes sieve loops
+10 pts 15m
Math & Number Theory easy

Prime Factorization

Return a sorted list of prime factors of a positive integer, including repeated factors.

prime math loops
+10 pts 15m
Math & Number Theory easy

Count divisors

Compute the number of positive divisors of a given integer using its prime factorization.

divisors prime factorization math
+10 pts 15m
Math & Number Theory easy

Sum of divisors

Given an integer n, return the sum of all its positive divisors.

divisors math number-theory
+10 pts 15m
Math & Number Theory easy

Abundant Number Check

Implement a function to check whether a given integer is abundant: sum of proper divisors exceeds the number.

math divisors number-theory
+10 pts 15m
Math & Number Theory easy

Armstrong Number Check

Implement a function that checks if a given integer is an Armstrong number.

arithmetic number-theory validation
+10 pts 10m
Math & Number Theory easy

Pentagonal Number

Given a positive integer n, return the nth pentagonal number using the formula P(n) = n(3n - 1)/2.

math formula integer
+10 pts 10m
Math & Number Theory easy

Partition function

Write a function that returns the number of ways to write a positive integer as a sum of positive integers (order irrelevant).

math recursion memoization
+12 pts 15m
Math & Number Theory easy

Multiply without multiply

Write a function that multiplies two integers using only addition, subtraction, and bit shifts — no * operator.

multiplication bit-manipulation arithmetic
+8 pts 12m

Showing 12 challenges · Math & Number Theory

Math & Number Theory — Python coding challenges

What you will find here

This page lists math & number theory challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.

Challenges vs tutorials and quizzes

Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.