largeprimes: 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/largeprimes - from package: perl-Crypt-Primes

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

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