= Unit-integral normalization of a B-spline
{title2=$\int M_i(t)\,dt=1$}
For strictly increasing <spline knots>, $M_i(t)=k[t_i,\ldots,t_{i+k}](\cdot-t)_+^{k-1}$ is a nonnegative integral-normalized <B-spline>. Integrating the <truncated power function> over its <support> replaces its <spline knot> value by $(u-t_i)^k/k$. The order-$k$ <divided difference> of this degree-$k$ <polynomial> is its <leading coefficient> $1/k$. Multiplying by the prefactor $k$ in $M_i$ gives integral one. The corresponding partition-normalized <B-spline> is $N_i=(t_{i+k}-t_i)M_i/k$.
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