The phrase "a formula under which" is correct and usable in written English.
It can be used when referring to a specific set of conditions or rules that govern a particular process or situation.
Example: "The project will be executed according to a formula under which all team members must contribute equally to the final outcome."
Alternatives: "a framework in which" or "a method by which".
We must try to find a formula under which we can live together in dignity.
The bill is expected to create a formula under which companies with big past liabilities will contribute more.
The royalty figure is based on a formula under which Hyundai pays North Korea a fee of $100 a day for each tourist.
A formula under which the United States would provide the North with such aid was the focus of negotiations in the final weeks of Bill Clinton's presidency.
Ten months after the United States lost its seat on the United Nations Human Rights Commission, the panel's regional group of Western countries is wrestling with a formula under which such embarrassing surprises would not be repeated.
The government has devised a formula under which it will allow the Acehnese to keep a much higher proportion of their oil wealth than they have ever been offered before.
Some 18 months ago a unity government took shape five months after a "global political agreement" had laid out a detailed formula under which Mr Mugabe would remain president but share power with Morgan Tsvangirai as prime minister.
But there were doubts that she would gain power.Trade UnionEuropean Union foreign ministers approved a compromise formula under which free-trade talks with Mercosur could be launched at the June 28th-29th Rio de Janeiro summit between the EU and Latin American leaders.
They pointed to the British model, which has more stringent checks and a minimum repayment formula under which repayments are calculated on the basis of interest, fees and 1% of the principal.
The mechanics of Mr Wolfowitz's departure were set in motion on Wednesday evening when the board's bank devised a face-saving formula under which he would step down while shifting some of the responsibility for the pay rise - which violated bank rules - to an ethics committee.
To prevent a revolt after the recount is completed, the candidates have agreed on a power-sharing formula, under which the eventual loser will have the right to become prime minister — a new, powerful position — or to name one of his supporters to the job.
