# Calculus

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Find a series ∑a_n for which ∑(a_n)^2 converges but ∑|a_n| diverges

• Calculus -

Consider
1 - 1/2 + 1/3 - 1/4 + ... (alternating harmonic series)

1 + 1/4 + 1/9 + 1/16 + ... = π2/6

1 + 1/2 + 1/3 + 1/4 + ... diverges (harmonic series)

• Calculus -

thanks!!

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