Make and prove a conjecture about the value of the following expression:

1ⁿ - 2ⁿ + 3ⁿ - 4ⁿ + 5ⁿ - 6ⁿ + 7ⁿ - 8ⁿ + 9ⁿ

This is the final WMC of the school year - I hope you've enjoyed trying some of them! I'll continue to check entries until the solution for this problem is published, on the 1^st of August. I then won't check the WMC mailbox until September.

Have a great summer holiday!