It's early for the Russians and the others who celebrate Christmas on the 7th January, but to the rest - Merry Christmas!

I wish you a lot of fun and great performance in Beta round 48 and SRM 492!

Find x
5^x + 1 = 4^{sqrt(x*x + 1)}
Could someone help (I can write a program to approximate the value, I'm interested in the mathematical solution)?

Hi,
I couldn't figure out how to take advantage of some features:
- How can I add someone as a friend?
- How can I make a contest?
- What else can I do?