SOLUTION: fill in the blank of the sequence and the recursive definition 1 3 3 8 7 18 those are the term number so im missing 2,4,5,6 3, ,8, , , ,18

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Question 1178663: fill in the blank of the sequence and the recursive definition
1 3
3 8
7 18
those are the term number so im missing 2,4,5,6

3, ,8, , , ,18
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

The recursive formula
a%5Bn%5D=a%5B1%5D%2Bd%28n-1%29
1 |3
3|+8
7|+18

a%5B1%5D=3
8=3%2Bd%283-1%29
8-3=2d
2d=5
d=5%2F2
or
d=2.5
a%5Bn%5D=3%2B2.5%28n-1%29
check a%5B7%5D
a%5B7%5D+=+3+%2B+2.5+%287+-+1%29=18->true
so, we need
a%5B2%5D=3%2B2.5%282-1%29
a%5B2%5D=5.5
a%5B4%5D=3%2B2.5%284-1%29
a%5B4%5D=10.5
a%5B5%5D=3%2B2.5%285-1%29
a%5B5%5D=13
a%5B6%5D=3%2B2.5%286-1%29
a%5B6%5D=15.5

your sequence is:
3,5.5 ,8, 10.5,13 , 15.5,18