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Problem 19 - Entrance Test

The series Σ_{n=1}^{∞} (2n+1)⁄[n²(n+1)²] converges to

Correct: A

Partial fractions: (2n+1)⁄[n²(n+1)²]=1⁄n² – 1⁄(n+1)². Telescoping sum: 1⁄1²=1.