
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 \( a_{k} \) be the coefficient of \( x^{k} \) in the expansion of \( (1+2x)^{100} \), where \( 0 \leq k \leq 100 \). Find the number of integers \( r \) such that \( 0 \leq r \leq 99 \) and \( a_{r} < a_{r+1} \).

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