Coded triangle numbers
Problem 42
The nth term of the sequence of triangle numbers is given by, tn = ½n(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 two-thousand common English words, how many are triangle words?
from tools import load_data, is_triangle
def run():
count = 0
names = load_data(42).replace('"', '').split(",")
for name in names:
number = sum(ord(c) - 64 for c in name)
if is_triangle(number):
count += 1
return count