<zgrep> misle/rn @/|a+b@| = { \xe2\x88\x9a(a\xc2\xb2-b\xc2\xb2) if a\xc2\xb2-b\xc2\xb2 \xe2\x89\xa5 0 ; i\xe2\x88\x9a(a\xc2\xb2-b\xc2\xb2) if a\xc2\xb2-b\xc2\xb2 < 0 }

Algebraic number theory was invented by Fermat to prove his theorem, but he didn't have room to write it down.