What Is the Next Number in the Series 13, 18, 16, 21, 19?

24 comes next in this run of numbers. This would resemble adding five to a number and then taking two away. This can be deduced from the first three numbers in the sequence: 13 + 5 = 18 and 18 – 2 = 16.

Finding a pattern in a series of numbers makes it possible to predict numbers that appear far later, frequently without recording the complete series. There are further uses for pattern recognition, such calculating probability. Some series of numbers are so typical that they have names. The Fibonacci sequence is one instance where a number is the sum of the two numbers that came before it.

Misha Khatri
Misha Khatri is an emeritus professor in the University of Notre Dame's Department of Chemistry and Biochemistry. He graduated from Northern Illinois University with a BSc in Chemistry and Mathematics and a PhD in Physical Analytical Chemistry from the University of Utah.


Please enter your comment!
Please enter your name here

Read More