I need to find a formula (not using Goal Seek or Solver) to find what regular monthly payments need to be made to achieve a target amount where the payments increase every year by a fixed %. The known information - as an example only - is as follows:

Target Amount: £1,000,000
Term: 12 years 7 months
Payment frequency: Monthly (but could also be annual)
Payments to Increase: Annually (assume on anniversary of 1st payment)
Payments increase by: 3% p.a.
Annual Growth Rate: 4% p.a. compound

I obviously need to know the starting payment but it would also be helpful to know the amount of the final payment. This is to calculate how much someone needs to start saving into a pension now to achieve their retirement goal where payments are linked to salary which it is assumed will increase at 3% p.a. The whole fund will grow at say 4% p.a.

I have searched high and low for this solution so any help will be very much appreciated.

Flossy129