You can use Apple’s Numbers app for sophisticated spreadsheet work. But where it falls short—as does Microsoft Excel—is at cleaning up data that’s in the spreadsheet. Where Microsoft Word lets you use ...

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

Two thousand years after the Indian mathematician and poet Acharya Pingala first described it, the Fibonacci sequence is still showing up in new places. The series—in which each number is the sum of ...

DEAR BONNIE: I have been seeing the number sequence 333 for the last two days. Those numbers hold a deep meaning for me, as that is the exact time my dad passed away. Who do you think is sending me ...