Originally posted by twilight2007
Wow...for some reason I thought 5 + 8 = 11...

Anyways...this problem is difficult since I can't use subscripts, but I'll try my best (and not make a simple mistake).

The pattern is (number)(number+1) = next number. The first numbers are decreasing by one as you go down. The next sequence (down) would be -5, 20, 420, ...

If I'm correct, then the third line is flawed; it should be 2, 6, [b]42, ...[/b]

Correct -although the actual formula I used was:

(number^2) + number = next number

But if you expand the brackets you get:

(number)(number+1) = next number.

So the two formulas are the same.