Is There a Missing Number in This Sequence?

[rootX]

http://aycu11.webshots.com/image/27370/2003197943184046097_rs.jpg

http://aycu11.webshots.com/image/27370/2003197943184046097_rs.jpg

 

[proton]

no, there shouldn't be a 2 because it cancels with the 2 in the denominator:

(1/v)[(2x)/(2sqrt(l^2 + x^2))]

 

[rootX]

no, there shouldn't be a 2 because it cancels with the 2 in the denominator:

(1/v)[(2x)/(2sqrt(l^2 + x^2))]

oh thank you!

 

[proton]

your welcome