Question

A playground is being designed where children can interact with their friends in certain combination i have the answer i need to know how to find the recursive equation that represents the pattern

Answer 1

an = an – 1 + 3(n – 1)
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verify:
a3=9
a4 = a3+3(4-1)
a4 = 9 +3(3) = 18

Answer 2

18=answer

Answer 3

Post the entire question.

Answer 4

A playground is being designed where children can interact with their friends in certain combinations.

If there is 1 child, there can be 0 interactions.
If there are 2 children, there can be only 1 interaction.
If there are 3 children, there can be 4 interactions.
If there are 4 children, there can be 9 interactions.

Which recursive equation represents the pattern?

Answer 5

Answer?