9! * 9! is not the number of boards, that is a bad estimate. If you don't account for symmetries, rotations, re-numberings and other things, the number of boards is 6.7e21. Even if you could check a full board in a nanosecond (which you can't) enumerating that number would take more than 200,000 cpu-years.
The paper linked to in the OP's article says: "Due to the sheer number of sudoku solution grids a brute force search would have been infeasible, but we found a better approach to make this project possible. Our software for exhaustively searching through a completed sudoku grid, named checker, was originally released in 2006. However, this first version was rather slow. Indeed, the paper [1] estimates that our original checker of late 2006 would take over 300,000 processor-years in order to search every sudoku grid."
The estimate in the comment (9!*9!) seems to be implying a simple enumeration, not a complex strategy of symmetry-folding. But even if you do reduce the enumeration, the authors of that paper say their software requires 800 CPU years. I'm not making any claims about whether getting that down to a day might be possible, but I wish you good luck. By all means, show everyone how to do it with a proper implementation and a large cluster! ;)
The paper linked to in the OP's article says: "Due to the sheer number of sudoku solution grids a brute force search would have been infeasible, but we found a better approach to make this project possible. Our software for exhaustively searching through a completed sudoku grid, named checker, was originally released in 2006. However, this first version was rather slow. Indeed, the paper [1] estimates that our original checker of late 2006 would take over 300,000 processor-years in order to search every sudoku grid."
https://arxiv.org/pdf/1201.0749.pdf
The estimate in the comment (9!*9!) seems to be implying a simple enumeration, not a complex strategy of symmetry-folding. But even if you do reduce the enumeration, the authors of that paper say their software requires 800 CPU years. I'm not making any claims about whether getting that down to a day might be possible, but I wish you good luck. By all means, show everyone how to do it with a proper implementation and a large cluster! ;)