olymmath

Putnam 2020 A3

  • Session A

Let a0=π/2a_0 = \pi/2, and let an=sin⁡(an−1)a_n = \sin(a_{n-1}) for n≥1n \geq 1. Determine whether ∑n=1∞an2\sum_{n=1}^\infty a_n^2 converges.

Curated text Kedlaya Putnam archive. Quoted with source.

Solutions

Human solution Solution 1 by Manjul Bhargava, Kiran Kedlaya and Lenny Ng

The terms of the source let olymmath link to this solution but not copy it. Read the solution (Kedlaya Putnam archive).

Locator putnam/2020/a3 · Tag K7R4HRAGZZ · Edit this page on GitHub · Keys: j next, k previous