PE 0002: Even Fibonacci Numbers
Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with
By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms.
Step-by-Step
Since this is another simple one, we'll start with another simple solution.
Odds and Evens
The first thing to notice is that only every third element of the sequence will be even. This is because of the (ODD ODD EVEN)-repeating pattern which will always appear in recurrent sums like this:
| odd | odd | even | odd | odd | even | odd | odd |