Owlet puzzle #38
Released Wednesday, August 12, 2026 UTC
1618033
the answer for puzzle #38
The five clues
- A seven-digit prime under two million.
- A famous irrational constant, made integer.
- The first seven digits of the golden ratio φ = (1+√5)/2, written without a decimal point.
- The golden ratio to six decimals: 1.618033...
- Read φ ≈ 1.618033 as an integer.
Backstory
The digits of φ = (1 + √5)/2 ≈ 1.618033988…, decimal removed. The golden ratio satisfies φ² = φ + 1, equals the limit of F_{n+1}/F_n for Fibonacci numbers, and also equals 2·cos(π/5). It's the 'most irrational' number in the sense of its continued fraction expansion [1; 1, 1, 1, …].
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