kmahjongg: command not found

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 CentOS possible default full paths are:

/usr/bin/kmahjongg - from package: kdegames

You may install the required package with command yum install {package}

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