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Removed extra "inductive".
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John Stillwell
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A nice simple problem with natural inductive inductive structure is the [tower of Hanoi problem.] 1 It is not obvious that any solution exists, and it is hard to come up with one explicitly, until you assume that it is possible to move the top $n-1$ disks, after which it is obvious how to move $n$ disks.

There is in fact a "noninductive" solution, but since it takes $2^n-1$ steps, it is preferable not to think about it.

[Added later] Of course, there is really no such thing as a "noninductive" theorem about natural numbers because of the inductive structure of natural numbers themselves. However, the "right" induction in this case exponentially compresses the solution, by suppressing unnecessary details.

A nice simple problem with natural inductive inductive structure is the [tower of Hanoi problem.] 1 It is not obvious that any solution exists, and it is hard to come up with one explicitly, until you assume that it is possible to move the top $n-1$ disks, after which it is obvious how to move $n$ disks.

There is in fact a "noninductive" solution, but since it takes $2^n-1$ steps, it is preferable not to think about it.

[Added later] Of course, there is really no such thing as a "noninductive" theorem about natural numbers because of the inductive structure of natural numbers themselves. However, the "right" induction in this case exponentially compresses the solution, by suppressing unnecessary details.

A nice simple problem with natural inductive structure is the [tower of Hanoi problem.] 1 It is not obvious that any solution exists, and it is hard to come up with one explicitly, until you assume that it is possible to move the top $n-1$ disks, after which it is obvious how to move $n$ disks.

There is in fact a "noninductive" solution, but since it takes $2^n-1$ steps, it is preferable not to think about it.

[Added later] Of course, there is really no such thing as a "noninductive" theorem about natural numbers because of the inductive structure of natural numbers themselves. However, the "right" induction in this case exponentially compresses the solution, by suppressing unnecessary details.

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Source Link
John Stillwell
  • 12.4k
  • 15
  • 96
  • 118

A nice simple problem with natural inductive inductive structure is the [tower of Hanoi problem.] 1 It is not obvious that any solution exists, and it is is hard to come up with one explicitly, until you assume that it is possible to move move the top $n-1$ disks, after which it is obvious how to move $n$ disks.

There is in fact a "noninductive" solution, but since it takes $2^n-1$ steps, it is is preferable not to think about it.

[Added later] Of course, there is really no such thing as a "noninductive" theorem about natural numbers because of the inductive structure of natural numbers themselves. However, the "right" induction in this case exponentially compresses the solution, by suppressing unnecessary details.

A nice simple problem with natural inductive inductive structure is the [tower of Hanoi problem.] 1 It is not obvious that any solution exists, and it is hard to come up with one explicitly, until you assume that it is possible to move the top $n-1$ disks, after which it is obvious how to move $n$ disks.

There is in fact a "noninductive" solution, but since it takes $2^n-1$ steps, it is preferable not to think about it.

A nice simple problem with natural inductive inductive structure is the [tower of Hanoi problem.] 1 It is not obvious that any solution exists, and it is hard to come up with one explicitly, until you assume that it is possible to move the top $n-1$ disks, after which it is obvious how to move $n$ disks.

There is in fact a "noninductive" solution, but since it takes $2^n-1$ steps, it is preferable not to think about it.

[Added later] Of course, there is really no such thing as a "noninductive" theorem about natural numbers because of the inductive structure of natural numbers themselves. However, the "right" induction in this case exponentially compresses the solution, by suppressing unnecessary details.

Source Link
John Stillwell
  • 12.4k
  • 15
  • 96
  • 118

A nice simple problem with natural inductive inductive structure is the [tower of Hanoi problem.] 1 It is not obvious that any solution exists, and it is hard to come up with one explicitly, until you assume that it is possible to move the top $n-1$ disks, after which it is obvious how to move $n$ disks.

There is in fact a "noninductive" solution, but since it takes $2^n-1$ steps, it is preferable not to think about it.