How many squares are der in 9X9 sudoku??

Question

How many squares are der in 9X9 sudoku??

Answer 1

Oops, looks like a trick question !!

A)  9x9 sudoku, I assume you mean regular sudoku game, which has 3x3 boxes in them.

B)  Let us assume all cells of these sudoku are squares. Without this assumption, this question will not have a unique answer. I noticed that some sudoku grids are not really square.  Such as in http://www.subundle.com/ , their games have multiple puzzles in a single grid, and the cells are actually rectangles.  assumption will not be needed  the question is "how many rectangles?" instead of squares.

C)  There are all different sizes of squares now:

  1 big square: 9 cells length.

  4 smaller one -length =8 (Top-right, top-left,...)

  9 : length=7 cells (shift one each time)

16,25,36,49,64,81 squares for other smaller ones.

D)  Use formula to get the sum of N squares:

     Sum= N*(N+1)*(2N+1)/6  

(http://pirate.shu.edu/~wachsmut/ira/infi...

Double check by adding them up: 285

285 is the final answer.

Answer 2

So it would be 9x9x9=729

Wow that's a lot.

PS a regular 3x3 sodoku is 3x3x9=81