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Geometric Sum Proof

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Geometric Sum Proof

Give a proof by induction to show that for every non-negative integer n:

20 + 21 + 22 + ... + 2n = 2n + 1 - 1

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Problem by BogusBoy

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Sum of Integers Proof

1  = 1 =
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1 + 2 = 3 =
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1 + 2 + 3 = 6 =
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