User:Jqer/Sandbox

$$\displaystyle x_N^*\, =\, c_N / u_{N,N}$$; for (i = N-1; i >= 1; i--) $$\displaystyle x_i^*\,:=\,\left( c_i\,-\, \sum_{j=i+1}^N	u_{i,j}x_j^*\right)/u_{i,i}$$;