September 2017 Update

Task/Digital-root-Multiplicative-digital-root/Zkl/digital-root-multiplicative-digital-root-1.zkl

@@ -0,0 +1,7 @@
+fcn mdroot(n){ // Multiplicative digital root
+   mdr := List(n);
+   while (mdr[-1] > 9){
+      mdr.append(mdr[-1].split().reduce('*,1));
+   }
+   return(mdr.len() - 1, mdr[-1]);
+}

Task/Digital-root-Multiplicative-digital-root/Zkl/digital-root-multiplicative-digital-root-2.zkl

@@ -0,0 +1,14 @@
+fcn mdroot(n){
+   count:=0; mdr:=n;
+   while(mdr > 9){
+      m:=mdr; digitsMul:=1;
+      while(m){
+	 reg md;
+	 m,md=m.divr(10);
+	 digitsMul *= md;
+      }
+      mdr = digitsMul;
+      count += 1;
+   }
+   return(count, mdr);
+}

Task/Digital-root-Multiplicative-digital-root/Zkl/digital-root-multiplicative-digital-root-3.zkl

@@ -0,0 +1,15 @@
+println("Number:  (MP, MDR)\n=======  =========");
+foreach n in (T(123321, 7739, 893, 899998))
+  { println("%7,d: %s".fmt(n, mdroot(n))) }
+
+table:=D([0..9].zip(fcn{List()}).walk());  // dictionary(0:List, 1:List, ...)
+n    :=0;
+while(table.values.filter(fcn(r){r.len()<5})){ // until each entry has >=5 values
+   mpersistence, mdr := mdroot(n);
+   table[mdr].append(n);
+   n += 1;
+}
+println("\nMP: [n0..n4]\n==  ========");
+foreach mp in (table.keys.sort()){
+   println("%2d: %s".fmt(mp, table[mp][0,5])); //print first five values
+}