Need help with coding a function in Python

[Paul Rubin]

devers.meetthebadger.jason at gmail.com writes:
> http://imgur.com/a/rfGhK#iVLQKSW ...

> So far this is my best shot at it (the problem with it is that the n
> that i'm subtracting or adding in the if/else part does not represent
> the element's position...

Right, so can you figure out the element's position?  If yes, calculate
it and use it instead of n.