Coded Triangle Numbers ¶

First we read in the words:

In [1]:

with open("txt/0042_words.txt") as f:
    words = {w.strip('"') for w in f.read().split(",")}

We'll also write a simple function for testing if a word is a "triangle word". We'll make use of SageMath's built-in function for testing if a number is triangular.

In [2]:

def is_triangle_word(word):
    value = sum(ord(c) - ord('A') + 1 for c in word)
    return is_triangular_number(value)

(It's not difficult to apply the quadratic formula to write our own test for triangular numbers.)

Now we just test each word.

In [3]:

triangle_words = {w for w in words if is_triangle_word(w)}
len(triangle_words)

Out[3]:

Copyright (C) 2025 filifa¶

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