
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
Observe the following number array, what is the 20th number in the 20th row?

                          1

                     2   3   4

                 5   6   7   8   9

      10   11  12  13  14  15  16

17   18  19  20  21  22  23  24  25

…   …  …  …  …  …  …  …  …

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