{ "name": "Contrapositive Proof", "order": 5, "challenges": [ { "id": "59a5801209a6acac5983b602", "title": "Contrapositive proof", "description": [ "" ], "challengeSeed": [ "" ], "tests": [ "" ] }, { "id": "59a5801209a6acac5983a915", "title": "Congruence of integers", "description": [ "" ], "challengeSeed": [ "" ], "tests": [ "" ] }, { "id": "59a5801209a6acac5983a916", "title": "Mathematical writing", "description": [ "" ], "challengeSeed": [ "" ], "tests": [ "" ] } ] }