There are more than 10^11 phone numbers in a the space of 11 digits. You have to include trailing spaces. 0055123456 is different to 00055123456.
They used all 16 combinations of tones, so they would need to cover 17^11 numbers (including spaces) to get all 11 digit phone numbers.
Slashdot Mirror
There are more than 10^11 phone numbers in a the space of 11 digits. You have to include trailing spaces. 0055123456 is different to 00055123456. They used all 16 combinations of tones, so they would need to cover 17^11 numbers (including spaces) to get all 11 digit phone numbers.