Problems & Puzzles: Puzzles

Puzzle 516. Fifty nine years old Related to my current age, Farideh Firoozbakht poses the following nice puzzle: 59 is the only number greater than 1 with this property: 59 = 5*9 + pi(5*9) . Q1. Can you prove it? Q2. Has 59 other singular properties?

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On October 29, 2026, Bas van Dorst launched a massive attack on 61 puzzles (64 results), including this one. Please see his contribution to this puzzle on the page https://www.primepuzzles.net/puzzles/puzz_1288.htm

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