generate_sequence: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/lib/jellyfish/bin/generate_sequence - from package: jellyfish-examples

You may install the required package with command apt-get install {package}
Error in other languages:
generate_sequence: bevel nie gevind nie
generate_sequence: comandă negăsită
generate_sequence: comando não encontrado
generate_sequence: commande introuvable
generate_sequence: command not found
generate_sequence: käsku ei ole
generate_sequence: không tìm thấy lệnh
generate_sequence: komanda nerasta
generate_sequence: Kommando nicht gefunden.
generate_sequence: kommandot finns inte
generate_sequence: komut yok
generate_sequence: nie znaleziono polecenia
generate_sequence: níor aimsíodh an t-ordú
generate_sequence: no se encontró la orden
generate_sequence: no s'ha trobat l'ordre
generate_sequence: opdracht niet gevonden
generate_sequence: parancs nem található
generate_sequence: perintah tidak ditemukan
generate_sequence: príkaz nenájdený
generate_sequence: příkaz nenalezen
generate_sequence: команда не найдена
generate_sequence: командата не е открита
generate_sequence: 命令找不到
generate_sequence: コマンドが見つかりません