1. A non-transitory computer-readable storage medium that stores a program causing a first processor among a plurality of processors configured to perform LU factorization in parallel to execute processing comprising: generating a first panel by integrating a plurality of row panels among panels of a matrix to be subjected to the LU-factorization, the plurality of row panels being processed by the first processor; generating a second panel by integrating a plurality of column panels among the panels of the matrix, the plurality of column panels being processed by the first processor; and computing a matrix product of the first panel and the second panel.