## We can’t tell you why you would want to memorize e to 15 places, but we can tell you how

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MEMORIZE e TO 15 PLACES

We recently asked a large group of people the question

In the number

e, how many places to the right of the decimal does the string ‘1828459045’ first occur?

Many people replied “two”, which is wrong, but indicates that many people know that e is equal to

2.71828something

Assuming you, dear reader, know that much of *e*, you can memorize **an extra 10 digits** by exploiting the following coincidence:

After 2.71828 comes **another** 1828 followed by 45 90 45, which is easy to remember as the angles in an isosceles right triangle.

Try it: What’s *e* to 15 places?

Answer: 2.71828 1828 45 90 45