Question 177077
2, 9, 20, 35, ...


2 + 7 =  9 
9 + 11 = 20
20 + 15 = 35

11 is 4 more than 7 and 15 is 4 more than 11.

If this is the pattern, each new number should be increased by a number that is 4 more than the last increase and the next numbers would be:

35 + 19 = 54
54 + 23 = 77
77 + 27 = 104
 and the series is 2, 9, 20, 35, 54, 77, 104


What do you think?