You can put this solution on YOUR website!
Aren't those the numbers you have to fill in the computer in the hatch from LOST ? Just kidding :p
I don't see a pattern in it UNLESS that first 5 is the number 2.
So instead of 1,3,5,6,5,15,14,42
I would consider 1,3,2,6,5,15,14,42
This sequence does have a pattern: multiply by 3 and subtract 1 (over and over and over).