<entry id="2291787" stat="R" corpus="jmdict" type="jmdict">
<ent_corp type="jmdict">jmdict</ent_corp>
<ent_seq>2860176</ent_seq>
<k_ele>
<keb>証終</keb>
</k_ele>
<r_ele>
<reb>しょうしゅう</reb>
</r_ele>
<sense>
<pos>&n;</pos>
<field>&math;</field>
<s_inf>abbr. of 証明が終わった</s_inf>
<gloss>end of proof marker</gloss>
<gloss>QED</gloss>
</sense>
<info>
<audit time="2024-02-11 14:10:52" stat="A" unap="true">
<upd_name>Ben Bullock</upd_name>
<upd_email>...address hidden...</upd_email>
<upd_refs>Rudin p. 6 (see entry for 非正 for full details)</upd_refs>
</audit>
<audit time="2024-02-12 01:30:54" stat="A" unap="true">
<upd_diff>@@ -14,0 +15 @@
+&lt;gloss&gt;Q.E.D.&lt;/gloss&gt;</upd_diff>
</audit>
<audit time="2024-02-12 05:57:19" stat="A" unap="true">
<upd_uid>jwb</upd_uid>
<upd_name>Jim Breen</upd_name>
<upd_email>...address hidden...</upd_email>
<upd_detl>Maybe a contraction of 証明終り. I think we'd need evidence of its use before adding it.</upd_detl>
<upd_refs>Zero n-grams, not in JEs or kokugos. The EJs don't mention it in their QED entries. RP has '証明終り'の意味で証明の末尾に書く.</upd_refs>
</audit>
<audit time="2024-02-12 23:28:41" stat="A" unap="true">
<upd_name>Ben Bullock</upd_name>
<upd_email>...address hidden...</upd_email>
<upd_detl>In a mathematics text the marker of the end of the proof is used to aid the reader to distinguish between the proof's text and whatever remarks the author might add after the proof has finished. It's often marked with a black square or a white square like ■ or □ instead. This usage is restricted to mathematics texts of course, but it's commonly seen even on the internet. 

https://service.zkai.co.jp/books/toudai/pdf/k6.pdf
http://www.misojiro.t.u-tokyo.ac.jp/~murota/lect-kisosuri/cauchyseq041109.pdf
https://www.math.tsukuba.ac.jp/~tange/jugyo/18/slide.pdf

A lot of the PDFs found with Google seem to have the ability to search the text switched off, but there are examples here:

https://horibe.jp/PDFBOX/HD_pi.pdf

As far as I can tell, there are not many Japanese mathematics books available in online form, so what I'll do is go to the library and take some pictures of various random maths books. Hopefully that will be enough to "end the proof" that this is a real word.</upd_detl>
</audit>
<audit time="2024-02-13 03:55:47" stat="A">
<upd_uid>jwb</upd_uid>
<upd_name>Jim Breen</upd_name>
<upd_email>...address hidden...</upd_email>
<upd_detl>Thanks for those examples, Ben. I can see it being discussed in that context. I guess not many mathematical proofs turn up as web pages.
I'll lock it in with a note and reopen for further discussion, if any.</upd_detl>
<upd_refs>https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q14238433999
https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q10131595015</upd_refs>
<upd_diff>@@ -13,3 +13,3 @@
-&lt;gloss&gt;Marker of end of proof in mathematics&lt;/gloss&gt;
-&lt;gloss&gt;Quod Erat Demonstrandum&lt;/gloss&gt;
-&lt;gloss&gt;Q.E.D.&lt;/gloss&gt;
+&lt;s_inf&gt;abbr. of 証明が終わった&lt;/s_inf&gt;
+&lt;gloss&gt;end of proof marker&lt;/gloss&gt;
+&lt;gloss&gt;QED&lt;/gloss&gt;</upd_diff>
</audit>
<audit time="2024-02-13 03:56:06" stat="A" unap="true">
<upd_uid>jwb</upd_uid>
<upd_name>Jim Breen</upd_name>
<upd_email>...address hidden...</upd_email>
</audit>
<audit time="2024-02-13 09:02:47" stat="A" unap="true">
<upd_detl>A site:ac.jp search brings up some stuff.</upd_detl>
</audit>
<audit time="2024-02-13 20:09:32" stat="R">
<upd_uid>stephen</upd_uid>
<upd_name>Stephen Kraus</upd_name>
<upd_email>...address hidden...</upd_email>
<upd_detl>Fork</upd_detl>
</audit>
</info>
</entry>