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Two Geometric Series (Posted on 2003-07-14)

Find a geometric series of 3 or more positive integers, starting with 1, such that its sum is a perfect square.

See if you can find another such series.

See The Solution Submitted by Brian Smith

Rating: 3.6667 (6 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)

Halfway there

| Comment 5 of 11 |

From simple observation, I found a geometric factor of 3 to work with five terms:

1+3+9+27+81=121=11²

Posted by Bryan on 2003-07-14 06:51:51

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