Tagged: prime numbers

Paul Erdős

After reading The Man Who Loved Only Numbers: The Story of Paul Erdős and the Search for Mathematical Truth this summer, I came across a fantastic children’s book about Paul Erdős.  The Boy Who Loved Math: The Improbable Life of Paul Erdős by Deborah Heiligman with pictures by LeUyen Pham is an excellent introduction to the man who is well-known for his collaboration in mathematics.  Below is a photo of the cover and my favorite illustration in the book:

IMG_1232   IMG_1236

Below is a short clip from N is a Number, which is a fantastic glimpse of Paul Erdős and his life of collaboration in mathematics:

References:

Heiligman, D. (2013). The boy who loved math: The improbable life of Paul Erdős. New York: Roaring Brook Press.

Hoffman, P. (1998). The man who loved only numbers: The story of Paul Erdős and the search for mathematical truth. New York: Hyperion.

smith numbers

Prime numbers have been a popular topic in the news.  Below is a strip about working with composite and prime numbers, using what are called Smith Numbers.  Smith Numbers are composite, but identified when the sum of the individual digits in the number are equal to the sum of the prime factors!

Now let’s take a look at 27.  The number 27 is probably most easily identified by school children as being 9 • 3. However, 9 is composite, so instead let’s take the 9 and look at it as 3 • 3.  Now we have 27 taken as 2 + 7, which is 9, and 3 + 3 + 3, which is also 9.

For the number 27: 2 + 7 = 3 + 3 + 3

Can 71 be a Smith Number?

References:

Caldwell, C. (2013). Smith number from The Prime Glossary http://primes.utm.edu/glossary/xpage/SmithNumber.html Accessed 11 June 2013.

Hoffman, P. (1998). The man who loved only numbers: The story of Paul Erdos and the search for mathematical truth. New York: Hyperion.

Weisstein, Eric W. “Smith Number.” From MathWorld–A Wolfram Web Resource. http://mathworld.wolfram.com/SmithNumber.html Accessed 11 June 2013.