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Fibonacci sequence generator
Exact values using BigInt — no precision loss even at large terms.
How it works
The sequence is built iteratively starting from [0n, 1n], with each new term computed as the sum of the previous two using JavaScript's BigInt type instead of regular numbers, so every value stays exact no matter how many digits it grows to.
FAQ
- Why use BigInt instead of regular JavaScript numbers?
- Regular JS numbers lose precision above 2^53 (Number.MAX_SAFE_INTEGER), which the Fibonacci sequence exceeds well before the 100th term. BigInt does exact, arbitrary-precision integer arithmetic, so every term shown is exact rather than rounded.
- Why is the term count capped at 1000?
- It's not a precision limit — BigInt keeps every digit exact no matter how large. The cap exists because the 1000th Fibonacci number already runs past 200 digits, and beyond that the output list just gets long and slow to render for no practical benefit.
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