The sequence below contains terms that doesn't have any perfect square factors (except 1). 2, 3, 5, 6, 7, 10, 11, 13, 14, 15...
What is the sum of the square-roots of the terms starting from 2 to the largest two-digit term?
408.59
see attached picture for solution, red highlighted are excluded numbers
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?