diff --git a/2017-03-14/jo-so_euler87_func.js b/2017-03-14/jo-so_euler87_func.js
index ab2b7c3..f131ccb 100755
--- a/2017-03-14/jo-so_euler87_func.js
+++ b/2017-03-14/jo-so_euler87_func.js
@@ -48,7 +48,7 @@ Array.prototype.cross = function (other, op) {
 // print([1, 2].cross([3, 4], (a, b) => a + b));
 
 let primeNumbers = [2,3,5,7,11,13,17,19];
-let limit = 5e7;
+const limit = 5e7;
 
 for (let num = primeNumbers[primeNumbers.length - 1] + 2;
      num <= Math.sqrt(limit); num += 2) {
diff --git a/2017-03-14/jo-so_euler87_iterator.js b/2017-03-14/jo-so_euler87_iterator.js
index 75a0d3c..ac62135 100755
--- a/2017-03-14/jo-so_euler87_iterator.js
+++ b/2017-03-14/jo-so_euler87_iterator.js
@@ -74,7 +74,7 @@ let primeNumbers;
 
 // print(Array.from(function* () { for (let x of primeNumbers()) { if (x > 50) return; yield x; } }()));
 
-let limit = 5e7;
+const limit = 5e7;
 
 function* pnPower(exp) {
     for (let e of primeNumbers()) {