
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
It is known that for the arithmetic sequence $\{a_n\}$, it satisfies $a_3 = 5$ and $a_1, a_2, a_4$ form a geometric sequence.
  (Ⅰ) Find $a_n$;
  (Ⅱ) If the common difference of the sequence $\{a_n\}$ is a non-zero constant, and $b_n = \frac {25}{a_{n} \cdot a_{n+1}}$, let the sum of the first n terms of the sequence $\{b_n\}$ be $T_n$, find the minimum value of $\lambda$ when $T_n \leq \lambda$ holds true for all $n$.

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