&lt;<span class="keyword">typename</span> dtype1, <span class="keyword">typename</span> dtype2&gt;</div>
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<div class="line"><a id="l00057" name="l00057"></a><span class="lineno"><a class="line" href="namespacenc_1_1special.html#a614d69a09535948c87124fe5662452dc">   57</a></span>    <span class="keyword">auto</span> <a class="code hl_function" href="namespacenc_1_1special.html#a614d69a09535948c87124fe5662452dc">bessel_kn</a>(<a class="code 