Q: 70 (IAS/2009)

While adding the first few continuous natural numbers, a candidate missed one of the numbers and wrote the answer as 177. What was the number missed ?
question_subject: 
Maths
question_year: 
2009
question_exam: 
IAS
question_sub_subject: 
Mathematics
question_topic: 
Mathematics
stats: 
0,176,192,96,56,176,40