Formal Book

9 Four times π2/6

Theorem 9.1 Euler’s series: Proof 1
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n11n2=π26
Proof
Theorem 9.2 Euler’s series: Proof 2
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k01(2k+1)2=π28
Proof
Theorem 9.3 Euler’s series: Proof 3
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n11n2=π26
Proof
Theorem 9.4 Euler’s series: Proof 4
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n11n2=π26
Proof
Theorem 9.5 Four proofs of Euler’s series

Collecting the proofs from the chapter

Proof