Question

How to solve?
An = An-3+3.3
= An-(n-1)+(n-1).3
=2+(n-1).3

Answer 1

Is A a constant?

Answer 2

Capital letters are usually used to describe a constant. I don't see how the first step lead to the second step either.

Answer 3

Clearly he put the lime in the proverbial coconut, shook it up, and something fell out during the shaking process.

Answer 4

No, that is a base n.

Answer 5

@nroprstar
The notation An reminds me of the symbol used to represent the nth term of an arithmetic sequence. It is read as a-sub-n.

The attached file shows what I am attempting to write.