Matrix in Java and MySQL using Spring + Hibernate

I am developing a web application using Java + Spring + Hibernate + MySQL.

I need to make a matrix that has as non-consecutive numbers rows like 1, 2, 3, 5, 10, 20, 30, 50, 100, etc. And something similar for columns (100, 150, 200, 300, 500, 1000, 1500, ...).

I was following this example but I do not know if I can do the following search: I have i_data = 27 and j_data = 278. I have to get the nearest integers. In this case, i = 30, j = 300, and with these numbers obtain the data of the matrix.

Any suggestions? I was told to try key embedabble but I do not know how.