# Quasi-random sequence on the unit $2$-sphere for Monte-Carlo based method

Please forgive my possible misuse of the appropriate definitions. I'm looking for a quasi-random sequence of directions in the unit $2$-sphere, to be used in a Monte-Carlo method to calculate an integral over the entire $4 \pi$ solid angle.

I'm currently using a Monte-Carlo approach for the calculation of global illumination for a 3d application, using pseudo-random numbers from a standard software package. The thing is that the convergence is too slow. I've read about it in Wikipedia, and found out that by using quasi-random sequences (like the Sobel sequence) I could improve the convergence speed from $\frac{1}{\sqrt{N}}$ to $\frac{1}{N}$. Is this correct?

NOTE: Please if there is some typing error in the math, I'll appreciate an editor's help.

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