/* On the sheet, the slice is a[0, 2, 4, ..., 16][2-10][1-9]. */
/* Below, the slice is a[0-8][2-10][1, 3, 5, ..., 17]. */
MPI_Type_vector(9, 1, 2, MPI_INT, &oneslice);
/* On the sheet, the slice is a[0, 2, 4, ..., 16][2-10][1-9]. */
/* Below, the slice is a[0-8][2-10][1, 3, 5, ..., 17]. */
MPI_Type_vector(9, 1, 2, MPI_INT, &oneslice);