orblist: 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/x86_64-linux-gnu/gap/pkg/guava/bin/leon/orblist - from package: gap-guava-bin

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