seqcons: 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/lib/seqan/bin/seqcons - from package: seqan-apps

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

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