
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
Let the sum of the first n terms of an arithmetic sequence {a_n} be S_n. If S_15 > 0 and S_16 < 0, determine among the ratios S_1/a_1, S_2/a_2, ..., S_15/a_15, which one is the largest.

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