Hello,

In the above question, 13, 17, 19, 23,... if we observe the trend then,

• 13
• 13 + 4 = 17
• 17 + 2 = 19
• 19 + 4 = 23

We observe that, the trend is, ( x + 4 ), ( x + 2 ), ( x + 4 ), and so on

Hence, the next numbers will be,

• 23 + 2 = 25
• 25 + 4 = 29
• 29 + 2 = 31
• 31 + 4 = 35 and so on..

i.e., the series will be, 13, 17, 19, 23, 25, 29, 31, 35,...

Best Wishes.