KenKen, which began appearing in The New York Times in February, is a new numerical logic puzzle from Japan. The name means loosely “cleverness squared.”

KenKen shares some properties with sudoku. Each is a pure logic challenge in which numbers are filled in the squares of a grid. Unlike sudoku, though, in which the numbers act solely as symbols (letters or pictures would work as well), KenKen requires arithmetic.

The rules are simple: Fill the grid with digits so as not to repeat a digit within any row or column, and so the digits within each heavily outlined box (called a cage) go together using the arithmetic operation shown to make the target number indicated.

Directed by New York Times Crossword Puzzle Editor Will Shortz, the American Crossword Puzzle Tournament is the nation’s oldest and largest crossword competition. Solvers tackle eight original crosswords created and edited specially for this event. Scoring is based on accuracy and speed. Prizes are awarded in more than 20 categories, including a $5,000 grand prize. Evening games, guest speakers, and a wine and cheese reception allow solvers to meet each other in a relaxed and entertaining atmosphere.

I am on a quest to become a contestant on the Puzzle on the Air segment of National Public Radio‘s morning news program Weekend Edition Sunday. During this segment, New York Times crossword puzzle editor and NPR puzzlemaster Will Shortz leads one lucky contestant on an on-air challenge of wordplay.

It’s remarkably easy to enter. Just solve the listener challenge given on the program and submit your answer to http://www.npr.org/puzzle before 3:00 p.m. Eastern time on Thursday. The contestant is chosen at random from all of the correct answers received before that week’s deadline.