[chaitanyav]

Product of Lucas Numbers Algorithm - "A fast algorithm for computing large Fibonacci numbers" -https://pdfs.semanticscholar.org/9652/9e1fedb0a372b825215c7b...

[chaitanyav]

Also wrote a gem that implements this algorithm here https://github.com/chaitanyav/fibonacci

[user2994cb]

That's nice. Here's a (recursive) Python implementation:

http://ideone.com/z1sUp4