InvariantMath

Problem & solution exchange

PROBLEMS

A living board for students, mentors, and aspiring researchers: share a question, a challenge, a technique, a counterexample, or a result worth understanding properly. Strong threads often grow into reading groups, mini-projects, and research directions.

— Problems
— Unanswered
Browse research threads, funded challenges, and method-heavy discussions in one board. Paid challenge cards surface immediately when a sponsor secures a reward.
Hall of Fame Original questions, beautiful explanations, and unusually clear mathematical work earn a place here. Each item is accompanied by a curator note so the recognition teaches as much as it celebrates.
Sponsored Problems Some challenges now include sponsor-funded rewards. Look for bounty badges and funding tags directly on the board.
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Share a problem. Start a thread. Plant a research seed.

Bring something worth thinking about: a tricky example, a “why does this step work?” question, a clean theorem, a counterexample, or a short challenge that reveals a method. Research-minded posts are welcome: conjectures, extensions, “what changes if we weaken the hypothesis?”, literature pointers, or links between topics. Not a place for copy-paste homework — make it discussable, and explain your reasoning.

Browse archive
Submit a problem →
Best opening line: “Here’s what I tried — where did my logic bend?”

How to use this board

  • • Open a title → read carefully → join the discussion thread.
  • • Write maths cleanly with LaTeX (MathJax is on for titles + solutions).
  • • Tag your post so the right people find it (level tags are welcome).
  • • Research vibe: share references, define terms, and explain why a step is valid.

Tracks & recurring threads

  • • ODEIntBee warm-ups (speed + technique)
  • • Research corner (conjectures, extensions, paper-to-problem threads)
  • • Proof clinic (definitions, lemmas, and “why this step is valid”)
  • • Classics & contests (beautiful problems that teach methods)

Paid challenge guide

  • • Reward badge means the sponsor attached a visible bounty.
  • • Funded means the reward has already been paid upfront.
  • • Challenge threads can include screenshots, diagrams, and external file links.
  • • Strong responses here are meant to become visible proof-of-work.

Hall of Fame ethos

  • • We celebrate originality, not just speed: a fresh question can be as valuable as a polished solution.
  • • Curator notes explain why something was selected, so recognition doubles as mathematical guidance.
  • • Outstanding answers are chosen for exposition, insight, elegance, or a method others can learn from.
  • • The goal is to reward serious craft and make high-quality mathematical work visible to the whole board.