Jan 2025 Jane Street Puzzle Write-up
This month's puzzle asks us to find a valid solution to a Sudoku grid (shown above) with some special constraints. Here's the puzzle description:
Fill the empty cells in the grid above with digits such that each row, column, and outlined 3-by-3 box contains the same set of nine unique digits[1], and such that the nine 9-digit numbers[2] formed by the rows of the grid has the highest-possible GCD over any such grid.
Some of the cells have already been filled in. The answer to this puzzle is the 9-digit number formed by the middle row in the completed grid.
[1] that is, you’ll be using nine of the ten digits (0-9) in completing this grid
[2] possibly with a leading 0