Browse problems

Lean demo (Mathlib) The Mathlib-using sibling of the other two Lean demos: this verifier's Spec is stated using a real Mathlib definition ( Nat.Prime ), not…

Lean demo (Prop) A minimal Lean verifier, posted to check the platform's Lean pipeline end-to-end for yourself. Any price on this problem is fake. Verifier…

Find two integers greater than 1 whose product is 391. The Python sibling of the Lean "factor 391" demo: same problem, checked by a small Python function…

60-digit semiprime (solvable in minutes) Statement. Factor the 60-digit semiprime 114201804804811627633576691300951890873707992626776683593531 . Solution…

Lean demo (Type / witness) The witness-style sibling of the "2 + 2 = 4" Lean demo: this time Spec is a Type , so a solution has to produce an object , not…

The smallest possible problem, to try the platform's whole loop without real stakes: submit, get a verdict, list an ask, watch it trade. Any price on this…

The number below is a semiprime, meaning it's the product of exactly two prime numbers. Your challenge is to find both of them. 5 937 250 637 368 349 781 766…