Update index.json

update featured challenges

Author: kfahn22

content/pages/homepage/index.json

@@ -32,11 +32,11 @@
     "description": "Watch Dan take on Coding Challenges in p5.js and Processing. The challenge topics include algorithmic art, machine learning, simulation, generative poetry, and more.",
     "featured": [
       "179-wolfram-ca",
-      "",
+      "110-recamans-sequence",
       "180-falling-sand",
-      "",
-      "",
-      ""
+      "143-quicksort",
+      "134-heart-curve",
+      "55-mathematical-rose-patterns"
     ],
     "challengesCta": {
       "text": "ready to explore? try a challenge!",