1. $2n$ is always even while $2n \pm 1$ is always odd.

2. $n!$ series, 1, 2, 6, 24, 120, 720, … Be comfortable withholding and subtracting 1 from it too, for example 2, 3, 7, 25, 121, 721.

3. APGP Series.

4. $2^n$ series, 2, 4, 8, 16, 32, 64, …

5. $3^n$ series, 3, 9, 27, 81, 243, …

6 $\frac{n(n+1)}{2}$ Triangular Numbers, 1, 3, 6, 10, …

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• […] into the GC, how to show increasing/ decreasing sequence. For conjecture, students may find this post helpful. How it can be hard, you can’t do your favourite MI if you can’t even do a […]