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Project Euler

A record of my Project Euler journey: every problem, completion status, on-site write-ups, and progress over time.

1008Total problems
522Solved
3On-site write-ups ↓
51.8%Completion

Project Euler write-ups

Complete solutions currently published on this site, including the original problem, formal statement, approach, and protected code and result.

3 on-site write-ups
#PE 001Multiples of 3 or 521 Feb 2013Read the on-site write-up →#PE 002Even Fibonacci Numbers21 Feb 2013Read the on-site write-up →#PE 003Largest Prime Factor22 Feb 2013Read the on-site write-up →

Solving journey

Change the time scale to compare new solves with cumulative progress.

First solve21 Feb 2013
Latest solve19 Aug 2026
Most active period2025 · 122 problems
01312613925222013: 23 problems2014: 79 problems2015: 109 problems2016: 129 problems2017: 165 problems2018: 200 problems2019: 233 problems2020: 239 problems2021: 250 problems2022: 251 problems2023: 262 problems2024: 335 problems2025: 457 problems2026: 522 problems20132014201520162017201820192020202120222023202420252026

Complete problem index

Every problem opens on this site. Purple: write-up available. Green: statement only, solved. Blue: statement only, unsolved.

Showing 10 / 1008
#0001Multiples of 3 or 5Write-up available21 Feb 2013#0002Even Fibonacci NumbersWrite-up available21 Feb 2013#0003Largest Prime FactorWrite-up available22 Feb 2013#0004Largest Palindrome ProductStatement only · Solved1 Mar 2013#0005Smallest MultipleStatement only · Solved21 Feb 2013#0006Sum Square DifferenceStatement only · Solved21 Feb 2013#000710 001st PrimeStatement only · Solved22 Feb 2013#0008Largest Product in a SeriesStatement only · Solved1 Mar 2013#0009Special Pythagorean TripletStatement only · Solved1 Mar 2013#0010Summation of PrimesStatement only · Solved1 Jun 2013

Problem numbers and titles come from Project Euler; solve status comes from a personal export. Project Euler ↗