Which one of the numbers does not belong in the following series1 - 2 - 5 - 10 - 13 - 26 - 29 - 48?

I'd say it's 48. To fit the pattern, it should be 58. If you take 1 and 2 and add them the answer is 3, you will use that answer several more times you will also add some numbers to them selves such as follows. 1+2=3 3+2=5 5+5=10 10+3=13 13+13=26 26+3=29 29+29=58 Thus making 48 the one that does not belong.