## When NOT to do sudoku

Anything goes, but keep it seemly...

### When NOT to do sudoku

Note to self: Don't do sudoku when angry, or during intense staff meeting discussions. It is likely to result in errors on puzzles.

enxio27

Posts: 484
Joined: 13 November 2007

### Re: When NOT to do sudoku

Or on a tiny grid with no room for pencil marks. Then the errors will result in still greater anger.

Bill Smythe
Smythe Dakota

Posts: 554
Joined: 11 February 2006

### Re: When NOT to do sudoku

I don't even bother with the tiny grids. I get most of my puzzles from online sources, which I print out myself using Richard's SudokuSolver (for variants) or SadMan Sudoku (for plain vanilla 9x9, because I can print them 4 to a page from the .SDC collection file). Most of the print puzzles I've come across are easy enough for me to do without pencil marks. If not, I save the puzzle for later printing from one of the two programs.

enxio27

Posts: 484
Joined: 13 November 2007

### Re: When NOT to do sudoku

Since you are a math major:

What is the next number in this sequence?

1, 3, 5, 7, ...

Hidden Text: Show
8. Those are the numbers with the letter E in their names.

Bill Smythe
Smythe Dakota

Posts: 554
Joined: 11 February 2006

### Re: When NOT to do sudoku

Smythe Dakota wrote:What is the next number in this sequence?

1, 3, 5, 7, ...

LOL! That's some serious thinking outside the box! I have a son would think just that way, and consistently get things "wrong" in school because of it.

enxio27

Posts: 484
Joined: 13 November 2007

### Re: When NOT to do sudoku

That's why, even though I'm a math person, I have always hated those "what's next in sequence" puzzles. There are often multiple reasonable answers, even if you don't go as far outside the box as I did!

In fact, given any N points (1,y1), (2,y2), (3,y3), ... (N,yN) on a coordinatized xy-plane, there always exists an (N-1)st degree polynomial (expressing y as a polynomial in x) that goes through all N of the given points. Just find that polynomial, and plug in N+1 for x, and bingo, you have the next element in the sequence.

Going further, if we change "(N-1)st degree" to "Nth degree", now there are infinitely many such polynomials, and any answer qualifies as a legitimate "the" next element in sequence.

Bill Smythe
Smythe Dakota

Posts: 554
Joined: 11 February 2006

### Re: When NOT to do sudoku

enxio27 wrote:
Smythe Dakota wrote:What is the next number in this sequence?

1, 3, 5, 7, ...

LOL! That's some serious thinking outside the box! I have a son would think just that way, and consistently get things "wrong" in school because of it.

I used to run into problems like that and always fail because my answer was different. It took quite a while to get used to going with the most "obvious" answer!
VSunk

Posts: 2
Joined: 07 June 2018

### Re: When NOT to do sudoku

I was going to say that the next number in the series is "obviously" p = 2^(277,232,917) − 1 because all 5 numbers are the roots of the polynomial (x-1)*(x-3)*(x-5)*(x-7)*(x-p) but I see that Smythe Dakota has stolen my thunder Leren

PS: What exactly is p? Well, it's apparently the largest proven prime number as of June 2018, having 23,249,425 digits. Leren
Leren

Posts: 3567
Joined: 03 June 2012