the third and fourth terms of the sequence are 21 and 38. If the second differences are a constant 2, what are the first five terms of the sequence?

2 answers

The 1st difference between terms 3 and 4 is 17
The differences and the sequence are thus

2 2 2 2 2 2 2 ...
13 15 17 19 21 23 ...
-7 6 21 38 57 78 101 ...
The first term of a sequence is 8. The first of the first differences is 3. The second differences are a constant 1. What are the first five terms of the sequence?