Data commit

Task/Mertens-function/XPL0/mertens-function.xpl0

@@ -0,0 +1,34 @@
+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