Enigma 1031: Security
21 December 2018
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From New Scientist #2187, 22nd May 1999
George’s new office has a security lock in which you have to key in a series of digits — all different — before you can open the door. Unfortunately, George is having difficulty committing this security number to memory.
So far, he has memorised a number comprising a selection of different digits from the security number. He has made a note of the memorised number on the memo sheet on which he was given the security number.
After studying the sequence yet again, he absent-mindedly left the memo lying around his house. When his wife found the piece of paper bearing just two numbers, she thought George has been trying to devise an “Alphametic” Enigma for New Scientist. Just for fun, she multiplied the numbers together and found that the product was a seven-digit number in which all the digits are the same.
What is George’s office security number?