Search for nucleon decay via <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>p</mml:mi> <mml:mo stretchy="false">→</mml:mo> <mml:mi>ν</mml:mi> <mml:msup> <mml:mi>π</mml:mi> <mml:mo>+</mml:mo> </mml:msup> </mml:math>

We present the results of searches for nucleon decays via <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mi>p</a:mi> <a:mo stretchy="false">→</a:mo> <a:mi>ν</a:mi> <a:msup> <a:mi>π</a:mi> <a:mo>+</a:mo> </a:msup> </a:math> and <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"> <d:mi>n</d:mi> <d:mo stretchy="false">→</d:mo> <d:mi>ν</d:mi> <d:msup> <d:mi>π</d:mi> <d:mn>0</d:mn> </d:msup> </d:math> using a <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"> <g:mrow> <g:mn>0.484</g:mn> <g:mtext> </g:mtext> <g:mtext> </g:mtext> <g:mi>Mt</g:mi> <g:mo>·</g:mo> <g:mi>yr</g:mi> </g:mrow> </g:math> exposure of Super-Kamiokande I-V data covering the entire pure water phase of the experiment. Various improvements on the previous 2014 nucleon decay search [], which used an exposure of <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"> <i:mrow> <i:mn>0.173</i:mn> <i:mtext> </i:mtext> <i:mtext> </i:mtext> <i:mi>Mt</i:mi> <i:mo>·</i:mo> <i:mi>yr</i:mi> </i:mrow> </i:math> , are incorporated. The physics models related to pion production and nuclear interaction are refined with external data, and a more comprehensive set of systematic uncertainties, now including those associated with the atmospheric neutrino flux and pion production channels, is considered. Also, the fiducial volume has been expanded by 21%. No significant indication of a nucleon decay signal is found beyond the expected background. Lower bounds on the nucleon partial lifetimes are determined to be <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"> <k:mn>3.5</k:mn> <k:mo>×</k:mo> <k:msup> <k:mn>10</k:mn> <k:mn>32</k:mn> </k:msup> <k:mtext> </k:mtext> <k:mtext> </k:mtext> <k:mi>yr</k:mi> </k:math> for <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"> <m:mi>p</m:mi> <m:mo stretchy="false">→</m:mo> <m:mi>ν</m:mi> <m:msup> <m:mi>π</m:mi> <m:mo>+</m:mo> </m:msup> </m:math> and <p:math xmlns:p="http://www.w3.org/1998/Math/MathML" display="inline"> <p:mn>1.4</p:mn> <p:mo>×</p:mo> <p:msup> <p:mn>10</p:mn> <p:mn>33</p:mn> </p:msup> <p:mtext> </p:mtext> <p:mtext> </p:mtext> <p:mi>yr</p:mi> </p:math> for <r:math xmlns:r="http://www.w3.org/1998/Math/MathML" display="inline"> <r:mi>n</r:mi> <r:mo stretchy="false">→</r:mo> <r:mi>ν</r:mi> <r:msup> <r:mi>π</r:mi> <r:mn>0</r:mn> </r:msup> </r:math> at 90% confidence level.