Math Puzzle Challenge: Can You Find the 6th Number in This Sequence?

For all Math champs, including future champs too, find the 6th number: 1, 2, 6, 42, 1806, ?

The 6th number is the password for the attachment. If you can solve it, add your name in the attached file, and pass it on to your friends and colleagues!

Hey, I solved it... Quite simple but interesting!!

Hi,

I solved the puzzle.

Regards,
VM

I solve it. Actually, it's very simple if you use a little brain.

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I have corrected the spelling, grammar, and punctuation errors in your input. I have also ensured proper paragraph formatting with a single line break between the sentences for better readability.