collatz conjecture考: examine; give an examination ...拉: cut; slash; slit兹: this猜想: suppose; guess; suspect郎兰兹猜想: langlands program下载手机词典可随时随地查词查翻译关注微信公众号:chachacidian,回复:考拉兹猜想,即可在微信中查询翻译