
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Given that the first four terms of an arithmetic sequence $\left\{ a_n \right\}$, which has distinct terms, sum up to $S_4=14$, and that $a_1, a_3, a_7$ form a geometric sequence.

(Ⅰ) Find the general formula for the sequence $\left\{ a_n \right\}$;

(Ⅱ) Let $T_n$ be the sum of the first $n$ terms of the sequence $\left\{ \frac{1}{a_n \cdot a_{n+1}} \right\}$, find $T_n$.

Present the answer in LaTex format: \boxed{Your answer}
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