Re: The set of necessary FISONs

On 1/28/2025 2:51 PM, FromTheRafters wrote:

Chris M. Thomasson expressed precisely :

On 1/28/2025 7:15 AM, WM wrote:

On 28.01.2025 13:45, Richard Damon wrote:

On 1/28/25 3:58 AM, WM wrote:

>

Many sets of FISONs whose union is N exist, and each of those sets has a first element.

>
Name the first element of only one of those sets which is required in that set.

>
Think of a tree:
>
>
          0
         / \
        /   \
       /     \
      1       2
     / \     / \
    3   4   5   6
....................
>
>
Well, the root node is 0. So, is that an origin point? ;^)

 I would say so, since the I in FISON is the initial element which is zero for the non-negative integers. His idea that things can be removed from the front of a FISON and still be a FISON seems doomed to fail.

Agreed. Now, this is fun. Another type of 2-ary tree:
........................
    \ /        \ /
    -1         -2
      \       /
       \     /
        \   /
         \ /
          0
         / \
        /   \
       /     \
      /       \
     1         2
    / \       / \
........................
To handle the negatives... ;^D