症状

anaconda3をosx(catalina)に入れて，AnacondaーNavigator.appからjupyter notebookをlaunchしたところ，terminalで以下のようなerrorが出て死にました．

$ /****/****/anaconda3/bin/jupyter_mac.command ; exit;
Failed to execute process '/****/****/anaconda3/bin/jupyter_mac.command'. Reason:
exec: Exec format error
The file '/****/****/anaconda3/bin/jupyter_mac.command' is marked as an executable 
but could not be run by the operating system.

解決法

terminalのdefault shellをfishにしたためです．jupyter_mac.commandの先頭に以下のshebang

#!/bin/bash

を追加して解決しました．

zshでも多分同じ(未検証).

ContinuumIO/anaconda-issues jupyter_mac.command is not executable with fish. #8222

source ~/Desktop/lecture_20f/math_python/jupyter_notebook_on_fish.org