int fila, columna;
int[][] pares = {{2, 4, 6, 8}, {10, 12, 14, 16}, {18, 20, 22, 24}};
System.out.println("Los 12 primeros números pares son:");
for (fila = 0; fila < pares.length; fila++) {
for (columna = 0; columna < pares[fila].length; columna++) {
System.out.printf("%3d ", pares[fila][columna]);
}
System.out.println();
}