logical problems

This is a mathematical challenge, and it's been said that: If you're an engineer, you should be able to solve it in (under) three minutes (more like 30 seconds), If you're an architect, in three hours; If you're a doctor, in six hours; If you're an accountant, in three months and if you're a lawyer, probably never. If you're good at math or logical problems, solve this challenge and the answer is the password to open the spreadsheet as per attached. If you open the spreadsheet as per attached, you can add your name to the hall of fame and send to your friends as a fun of game. What is the missing number in this logical series? 1, 2, 6, 42, 1806, ____??? The answer is the password to open the spreadsheet that is attached to this email. If you figure it out, open the spreadsheet, type your name in, save it and resend it to your friends. Good luck

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