<li>The <a href="/pkg/math/rand/v2/#Source"><code>Source</code></a>
interface now has a single <code>Uint64</code> method;
there is no <code>Source64</code> interface.

<li>Many methods now use faster algorithms that were not possible to adopt in <code>math/rand</code>
because they changed the output streams.

<li>The
<code>Intn</code>,
<code>Int31</code>,
<code>Int31n</code>,
<code>Int63</code>,
and