integer M ( 1+1000 );
integer K, Zero, Cross, N;
begin   \compute values of the Mertens function
\Generate Mertens numbers
M( 1 ) := 1;
for N := 2 to 1000 do begin
    M( N ) := 1;
    for K := 2 to N do M( N ) := M( N ) - M( N / K )
    end;
\Print table
Text(0, "The first 99 Mertens numbers are:^m^j");
Text(0, "   " );
K := 9;
for N := 1 to 99 do begin
    Format(3, 0);
    RlOut(0, float(M(N)));
    K := K - 1;
    if K = 0 then begin
        K := 10;
        CrLf(0);
        end
    end;
\Calculate zeroes and crossings
Zero  := 0;
Cross := 0;
for N :=2 to 1000 do begin
    if M( N ) = 0 then begin
        Zero := Zero + 1;
        if M( N - 1 ) # 0 then Cross := Cross + 1
        end
    end;
Text(0, "M(N) is zero ");  IntOut(0, Zero);  Text(0, " times.^m^j" );
Text(0, "M(N) crosses zero ");  IntOut(0, Cross);  Text(0, " times.^m^j" );
end