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- Jan 26, 2012

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Thank you to grgrsanjay for this idea.

Given the sequence where \(\displaystyle a_1=7\), \(\displaystyle a_2=77\), \(\displaystyle a_3=777\) and so on, derive a formula for summing the first n terms of the sequence.

Bonus: Prove through induction that this formula is valid.

Remember to read the POTW submission guidelines to find out how to submit your answers!

Given the sequence where \(\displaystyle a_1=7\), \(\displaystyle a_2=77\), \(\displaystyle a_3=777\) and so on, derive a formula for summing the first n terms of the sequence.

Bonus: Prove through induction that this formula is valid.

Remember to read the POTW submission guidelines to find out how to submit your answers!

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