
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 an arithmetic sequence {a<sub>n</sub>} that satisfies (n+1)a<sub>n</sub>=2n<sup>2</sup>+n+k, k∈R.
(1) Find the general term formula for the sequence {a<sub>n</sub>};
(2) Let b<sub>n</sub>=$$\frac {4n^{2}}{a_{n}a_{n+1}}$$, find the sum of the first n terms S<sub>n</sub> for the sequence {b<sub>n</sub>}.

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