Question

plz answer with explanation at the place of question mark​

Answer 1

we can take it as 1,5,13,29,61,125,?

now, 1×2+3 = 5

5×2+3 = 13

13×2+3 = 29

29×2+3 = 61

61×2+3 = 125

so,125×2+3 = 253 is the ans