
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
How many 2015-element subsets \( A \) are there of the set \( \mathrm{X}=\left\{1,2,3, \ldots, 5 \times 10^6\right\} \) such that the sum of the elements of any non-empty subset of \( A \) is not a multiple of 2016?

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