CURIOUS AND INTERESTING NUMBERS

BY

DAVID WELLS

4 stars out of 5 stars

The second sentence in the Introduction stated: “Archimedes promised the tyrant Gelon that he would calculate the number of grains of sand required to completely fill the universe, and did so.”

I was so intrigued by this statement that, while reading the book, I subconsciously looked for the answer, and was disappointed that I was not able to find it when I finished the book.

 This book claims to be the Dictionary of Curious and Interesting Numbers.  While the contents certainly justify the “curious” claim, how much of the numbers can be considered “interesting” is up to the individual reader.  Similarly, while “Dictionary” does reflect the contents, it is hard to look up a number you are interested.  For example, if you want to look up Fibonacci numbers, you will be hard put to know where to locate it in the body of the dictionary, unless you look it up in the index.  The author recognized this, and stated the difficulty in the Introduction.  In a conventional dictionary, one does not need to look up a word in the index.  Indeed, two dictionaries I own do not have index, one is Webster Dictionary and the other is Advanced Dictionary.

This “Dictionary” under review starts with -l and i, followed by 0 and many numbers that begin with 0, for example 0.0201030407 11… I leave it to the reader to find out why and whether this number is interesting.  After 0 comes the integer one and again followed by many numbers that begin with 1, for example1.060660,,,,  , Then it continues with 2,3  etc. until 79.  There is no 80. Presumably because no number with 80 on it is interesting.  It resumes from 81 until 121.  Then a gap again and resumes at 125. 

After about 1,000, the numbers that appear do not follow any pattern.  It ends with the number “3↑↑↑3   etc.“.   which has the name Grahm’s number.

Preceding the “Dictionary”, there is a list of mathematicians in chronological order..After the “Dictionary”, there are eight tables.  The reader learns, among other things, Pentagonal, Hexagonal, Heptagonal and Octagonal Numbers and The Prime Numbers less than 1000. However, it remains a challenge to find the answer posed by Archimedes – the number of grains of sand required to completely fill the universe.

In conclusion, if you are a number fan, you will learn much and find this book interesting.  If not, you are likely to find the contents perplexing and the organization confusing.