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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)

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2 solutions

| Comment 4 of 11 |

1 + 3 + 9 + 27 + 81 = 121 = 11^2
1 + 7 + 49 + 343 = 400 = 20^2

Posted by exoticorn on 2003-07-14 06:48:05

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