tricensus: 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/tricensus - from package: regina-normal

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

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