Consider the Cox-de Boor recursion formula for producing B-spline basis functions given a knot vector:
$N_{i,0}(u)=1 $ if $u_i\leq u < u_{i+1}$ otherwise, $=0$
$N_{i,p}(u)=\frac{u-u_{i}}{u_{i+p}-u_{i}}N_{i,p-1}(u)+ \frac{u_{i+p+1}-u}{u_{i+p+1}-u_{i+1}}N_{i+1,p-1}(u)$
Now, I read that B-splines can also be produced using recursive convolution instead of the recursion formula above. For example, see this page: http://www.chebfun.org/examples/approx/BSplineConv.html
Can someone explain if these two are related in any way, I am just not seeing it? And if so, how can I apply convolution to the knot spans of a knot vector to produce the same B-spline basis that we'd get by using the Cox-de Boor formula?