## When Frank Nelson Cole Factored A Large Number During A “Lecture”

For around 200 years, several mathematicians had surmised that the Mersenne number 267 – 1 may be prime. However, French mathematician Édouard Lucas proved in 1876 that 267 – 1 can be factored and hence, not a prime. However, he was unable to find its factors.

On October 31, 1903, Frank Nelson Cole, an American mathematician informed his fellow mathematicians that he would attempt to factorize 267 – 1 during a meeting of the American Mathematics Society. He went towards the chalkboard and proceeded to give an approximately one-hour “lecture”. Without uttering a single word, he began to calculate the value of 267 – 1 and he got 147,573,952,589,676,412,927. Moving to the other side of the chalkboard, he wrote 193,707,721 × 761,838,257,287 and he calculated the answer manually using long multiplication.

After Cole was finished multiplying the two large numbers, he was able to show that the answer equaled 267 – 1. Then he got back to his seat, not having said anything during the entire “lecture”. Despite the silence, his presentation was well-received by the audience who gave it a standing ovation.

Years later, when Cole’s friend, Eric Temple Bell, asked him how long did it take for him to factor the number, his reply was “three years of Sundays”.

My name Edmark M. Law. I work as a freelance writer, mainly writing about science and mathematics. I am an ardent hobbyist. I like to read, solve puzzles, play chess, make origami and play basketball. In addition, I dabble in magic, particularly card magic and other sleight-of-hand type magic. I live in Hong Kong. I blog at learnfunfacts.com. You can find me on Twitter @EdmarkMLaw and Facebook. My email is learnfunfacts@gmail.com
This entry was posted in Anecdotes, Mathematics and tagged , , , , . Bookmark the permalink.

### 8 Responses to When Frank Nelson Cole Factored A Large Number During A “Lecture”

1. craftysurf says:

Original “drop da mic”…..😎

Liked by 1 person

2. I wish I could have been there to experience the clicking silence.

Liked by 1 person

3. “three years of Sundays” — there is a whole poem in that phrase.

Liked by 2 people