sleighmon.R: 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 CentOS possible default full paths are:

/usr/share/R/library/nws/bin/sleighmon.R - from package: R-nws

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

On Debian possible default full paths are:

/usr/lib/R/site-library/nws/bin/sleighmon.R - from package: r-cran-nws

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