matho-primes: 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 Debian possible default full paths are:

/usr/bin/matho-primes - from package: mathomatic-primes

You may install the required package with command apt-get install {package}

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