#+TITLE: Even Fibonacci numbers

* Problem description

Each new term in the Fibonacci sequence is generated by adding the previous
two terms. By starting with 1 and 2, the first 10 terms will be:

1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...

By considering the terms in the Fibonacci sequence whose values do not
exceed four million, find the sum of the even-valued terms

(answer 4613732)

Add even fibonacci problem description.
Add even fibonacci problem description.
