Tic Tac Toe Pro vs Numerical Tic Tac Toe

The #1 Tic Tac Toe app for iOS just got better. Play against your Game Center friends or random opponents using our new turn-based multiplayer feature! Tic Tac Toe Pro supports one player and two player gameplay, so you can play against another human or against your iPhone. The AI for one player mode includes three difficulty levels, so you can play against a computer player that matches your skill level. A move randomization engine ensures that your iPhone won't keep making the same moves over and over again. Our new turn-based network play feature allows you to play up to 16 simultaneous network games against your Game Center friends or random network opponents over Wi-Fi or 3G. Tic Tac Toe Pro offers a host of exciting features, including: * Turn-based network play over Wi-Fi or 3G * Great graphics and exciting sound effects * Configurable player names and score tracking * Undo function * Automatic save when you get a phone call or exit the application Tic Tac Toe on the iPhone and iPod Touch has never been so exciting. Get Tic Tac Toe Pro today and join the fun!

Numerical tic-tac-toe is a variant of tic-tac-toe that replaces the traditional Xs and Os with odd and even numbers. Players alternate placing numbers, aiming to form a line that adds up to 15.  The game is played on a normal nine square tic-tac-toe board. The odd player begins with the numbers 1, 3, 5, 7, and 9. The even player begins with the numbers 2, 4, 6, and 8. Odd always goes first. The two sides alternate placing numbers on the board in empty squares. Numbers cannot be repeated. So, there will only ever be a single instance of each number on the board. The first player to put a number down that achieves a sum of 15 composed of three numbers in a row, column, or diagonal wins the game. Note, that two numbers adding to 15 is not sufficient. So, a 6 next to a 9 is not a win. *Features* - Play against an AI opponent - Play against a friend - Three levels of difficulty - Customizable colors *History* Numerical tic-tac-toe was invented in the late 1950s by American mathematician Ronald Graham. A similar game was contemporaneously invented by P.H. Nygaard. In 1990, George Markowsy wrote a computer program that solved numerical tic-tac-toe. He proved that 1 in the top middle slot is a winning first move for odd. In other words, in perfect play, odd wins the game. Markowsky published his findings in The Journal of Recreational Mathematics.