Erasable Games specializes in white board products designed to make games like Sudoku easy and fun.

## Erasable Games Weblog

(Sudoku in words and pictures)

## Archive for April, 2007

### Geometric Sudoku

Saturday, April 28th, 2007

A mapping of Geometric Shapes For Sudoku Purposes. Each n-gon shape contains the number of sides corresponding to its units digit.

### Shogi Sudoku

Saturday, April 21st, 2007

I have been a long time Shogi (Japanese Chess) player. The problem is too few worthy opponents. This may be due to the fact that playing Shogi for any length of time fosters frequent sacrifices, which totally ruins you for regular chess.

Shogi is played on a 9 x 9 square board and your pieces are pointing away from you. Your opponent’s pieces are pointing toward you. One major feature that distinguishes Shogi from Western Chess is that pieces that you capture become yours to play again anywhere unoccupied on the board. (pawns only drop onto your non-pawn lanes.) As a result, there are no draws in Shogi.

It took me about a month to recognize the Japanese characters reliably, without referring to the names and pictures. Once you study the characters, they are quite dissimilar from each other and have unique identification areas. While western chess emulates middle-ages warfare, Shogi is more a metaphor for aerial warfare a la World War 1 (and perhaps 2).

Other resources for this game include shogi.net, shogi.com, the Ricoh Shogi Club and the Computer Shogi Association which tracks the World Computer Shogi Championships.

For the last few weeks, I’ve been swamped with extra curricular activities which has constrained my writing here. I hope to resume in May.

### Sudoku Math

Saturday, April 14th, 2007

I am in debt to Theoni Pappas, whose Mathematics Calendar inspired this Sudoku variation. Her yearly wall calendars have the wonderful characteristic that each daily math problem shown has a solution that is that day’s number!

### Holographic Sudoku

Saturday, April 7th, 2007

This is a derivative of Twin Sudoku with only digits in each starting puzzle. A Book of such puzzles, called Unico Sudoku by Luigi Poderico is offered on the Lulu website. The introduction is written in the style of “Borat” (Amusing, not insulting).