Three is a Crowd Sudoku (Daily Sudoku League #93)

Welcome to a puzzle that plays with the idea of incorrect clues! This Three is a Crowd Sudoku is a unique variant that appeared in the 2014 Sudoku Grand Prix Championship, and I prepared this puzzle from my collection over a year ago. The puzzle looks similar to Outside Sudoku, but with a crucial difference: the clues outside the grid are given in triplets. The rule is that for each triplet, exactly one of the three digits is incorrect and does not belong in the contiguous box of that row or column. Furthermore, on each side of the grid, the nine incorrect numbers must all be different.

This means you must not only place digits correctly but also identify the one "crowd" digit in each triplet that doesn't belong. The puzzle is my 93rd contribution to the Daily Sudoku League and offers a fascinating and challenging twist on the classic outside clue system. It's perfect for solvers looking for a variant that requires careful deduction and pattern recognition.

Rules of the Three is a Crowd Sudoku

Classic Sudoku Rules apply. Additionally, external digits show the three numbers to be placed in the contiguous box of the corresponding row or column. Exactly one digit for each triplet, however, is incorrect. On each side of the grid (top, bottom, left, right), the nine incorrect numbers are all different.