Count the number of cell rows address from top to bottom?

Dear All

Example:
When C2 input 1 start from row A3 to the end of Other, D2 is Row address 3 , E2 is row address 6
When C2 input 2 start from row A3 to the end of Other, D2 is Row address 10 , E2 is row address 18
When C2 input 3 start from row A3 to the end of Other, D2 is Row address 22 , E2 is row address 27

D2 and E2 formula

Thanks for any help!