Question 10
The letters K, O, R, E, A, I, M, C form eight rows, with one K in the first, two Os in the second, and so on to eight Cs in the last. Starting at K, spell KOREAIMC by moving to the next row, directly below or to either neighbour, as shown by the bold path. One of the thirty-six letters is forbidden, reducing the number of paths to five hundred sixteen. Which letter is forbidden?
