
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
Integers \( n \) and \( k \) are given, with \( n \geq k \geq 2 \). You play the following game against an evil wizard. The wizard has \( 2n \) cards; for each \( i=1, \ldots, n \), there are two cards labeled \( i \). Initially, the wizard places all cards face down in a row, in unknown order. You may repeatedly make moves of the following form: you point to any \( k \) of the cards. The wizard then turns those cards face up. If any two of the cards match, the game is over and you win. Otherwise, you must look away, while the wizard arbitrarily permutes the \( k \) chosen cards and then turns them back face-down. Then, it is your turn again.

We say this game is winnable if there exist some positive integer \( m \) and some strategy that is guaranteed to win in at most \( m \) moves, no matter how the wizard responds. For which values of \( n \) and \( k \) is the game winnable?

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