What is the sum of the even numbers that are immediately followed by an odd number in the list below?
4 2 5 1 8 2 9 7 4 6 6 9 8
The digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 can be arranged into an addition sum to add up to almost any total, except that nobody has yet found a way to add up to 1984. However 9 digits can equal 1984 by an addition sum. Which digit is omitted?
