Library · Short Excursions · Logic puzzles and solvers
Posidoku
A Sudoku variant by Alf Smith with no number clues, only positional gold cells whose values must equal their row, column, or box position. Solved with Google's CP-SAT.
Standard Sudoku constraints plus a positional rule on gold cells (must equal row, column, or box position) and the negation on white cells. CP-SAT handles the lot. Worked solutions for the and puzzles are in the PDF.