program arithmetic_derivative;
    loop for n in [-99..100] do
        nprint(lpad(str lagarias(n), 6));
        if (col +:= 1) mod 10 = 0 then
            print;
        end if;
    end loop;

    loop for m in [1..20] do
        nprint("D(10^" + lpad(str m, 2) + ") / 7 = ");
        print(lagarias(10**m) div 7);
    end loop;

    proc lagarias(n);
        return if n<0 then
            -lagarias(-n)
        elseif n in {0,1} then
            0
        elseif forall d in {2..floor sqrt n} | n mod d /= 0 then
            1
        else
            (n div d)*lagarias(d) + d*lagarias(n div d)
        end;
    end proc;
end program;