newseq: 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/bin/newseq - from package: emboss

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