Even Fibonacci numbers

 1 --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:

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

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

 4 function list_iter()

 5     local n = 1000000

 6     local i = 1

 7     local j = 0

 8     return function()

 9         if(i < n) then

10             tmp = i + j

11             j = i

12             i = tmp

13             return i

14         end

15     end

16 end

17 

18 local sum = 0;

19 for i in list_iter() do

20     if(i % 2 == 0) then sum = sum + i end

21 end

22 print(sum)