Takebe's series for π²
Serie de Takebe para π²
- Date
- 1722 · confidence high
- Place
- Edo (Tokyo), Japan
- Credited to
- Takebe Katahiro
- People
- 👤 Takebe Kenkō1664–1739
- Field
- Knowledge & symbols
What was discovered
An infinite series expansion of the square of the arcsine, which gives π² and allowed π to be calculated to 41 decimal places. It is a result obtained independently 15 years before Euler.
It appears in the Tetsujutsu Sankei (1722); Euler published the same series in 1737.
What it led to
- high-precision calculation of π in Japan
- extrapolation techniques in wasan