Test your blink/short term memory!A number will be flashed for 1 to 5 seconds depending on the length of the number. Remember the number. Then input the number that was flashed.Difficulty levels from 4 to 20 digits. Good luck!Split number into 1 to 4 groupsAchievement table to keep track of your progressEmail your suggestions and comments to [email protected]: puzzle, brain, memory, digit span, number span