Question

This one is probably really easy I just don't see the sequence rule!

I dont even need the rule, just the next 3 numbers


-3,0,4,9, ?,?,?...


thank you!

Answer 1

15,22,30 are the next 3 numbers

Explanation:

-3,0,4,9,...

Add 3, then add 4, then add 5,

The next would be add 6

9+6 = 15

Then add 7

15+7 =22

Then add 8

22+8 = 30

The sequence is given by

an = 1/2 (n^2 + 3 n - 10)