Ok, first a really simple sequence, but for some reason this online page isn't accepting it.

Find a formula for the general termanof the sequence, assuming that the pattern of the first few terms continues. http://www.webassign.net/cgi-bin/sym...0text%28%7D%29

I'm putting in 5/(4^n) but it's not taking it. Either this input is messed up, or i'm missing something elementary.