In Typescript, write a function to solve the following.

The nth term of the sequence of triangle numbers is given by, tn=1/2n(n+1); so the first ten triangle numbers are: 1,3,6,10,15,21,28,36,45,55, By converting each letter in a word to a number corresponding to its alphabetical position and adding these values we form a word value. For example, the word value for SKY is 19+11+25= 55=t10. If the word value is a triangle number then we shall call the word a triangle word. Using words.txt (right click and 'Save Link/Target As...'), a 16K text file containing nearly twothousand common English words, how many are triangle words