formula for populating a cell based on another cell's value

Can anyone tell me whether there is a formula in Excel which will allow me to fill a cell with a value based on a value in another cell + 1?

So if cell A1 contains the value '1', the cell with the formula (let's say B1) would show '2'. Then if the value in A1 changes, B1 updates as well.

Any ideas/help would be much appreciated!