docs: public static final DenseMatrix64F get141Matrix(int order)
      {
          if (order < 2)
          {
              throw new IllegalArgumentException("order has to be at least 2 for 1 4 1 matrix");
          }
          double[] data = new double[order*order];
          for (int row=0;row<order;row++)
          {
              for (int col=0;col<order;col++)
              {
                  int index = row*order+col;
                  if (row == col)
                  {
                      data[index] = 4;
                  }
                  else
                  {
                      if (Math.abs(row-col) == 1)
                      {
                          data[index] = 1;
                      }
                      else
                      {
                          data[index] = 0;
                      }
                  }
              }
          }
          return new DenseMatrix64F(order, order, true, data);
      }