How Do I Cycle Through a Column in MySQL? (no replies)

Assume I have two tables as follows:

CREATE TABLE Example_Table(
`Number` INT PRIMARY KEY,
`Letter` CHAR(1));

CREATE TABLE Adder(
`Number` INT PRIMARY KEY,
`Value` INT);
And I input them with values as such

INSERT INTO Example_Table VALUES (1,'a'),(2,'b'),(3,'c'),(4,'d');
INSERT INTO Adder VALUES (1,3),(2,6),(3,1),(4,2);


I want to cycle through the Example_Table.Number column by adding the Values in the Adder table. I want to create a select statement to extract the primary keys of the resulting sums, but only within the range of the values under the Example_Table.

For example, I will add 3 (the first value under Adder) to the 1 under Example_Table.Number, giving a new value of 4 which the SELECT statement will call upon. There's no issue there. I then add the 6 (under Adder) to the 2 under Example_Table, giving a new value of 8. However, since 8 doesn't exist within the table, I'd like it to simply count 6 (so 3,4,1,2,3,4) and then cycle back to 4.

Any advice on how this could be done, please?