Thursday, June 18, 2009

142857 is an Interesting Number

A couple of days ago a colleague sent me this interesting number, 142857, via email. I performed a Google search on the number and I was surprised to see so many returns - 190,000. It even has its own wiki page. For additional information, here is the wiki page for this cyclic number - 142857.

Below is the email.

Subject: Interesting Numbers

Roy,

I want to let you know a weird number which is 142857.

Why?

142857 X 1 = 142857
142857 X 2 = 285714
142857 X 3 = 428571
142857 X 4 = 571428
142857 X 5 = 714285
142857 X 6 = 857142

See, the answers show all same numbers with different position.

142857 X 7 = 999999

142 + 857 = 999
14 + 28 + 57 = 99

142857 X 142857 = 20408122449
20408 + 122449 = 142857

Interesting, huh?