% Ackermann function
ack = proc (m, n: int) returns (int)
    if     m=0 then return(n+1)
    elseif n=0 then return(ack(m-1, 1))
    else            return(ack(m-1, ack(m, n-1)))
    end
end ack

% Print a table of ack( 0..3, 0..8 )
start_up = proc ()
    po: stream := stream$primary_output()

    for m: int in int$from_to(0, 3) do
        for n: int in int$from_to(0, 8) do
            stream$putright(po, int$unparse(ack(m,n)), 8)
        end
        stream$putl(po, "")
    end
end start_up