26

A basic solution is as the sequence


10

It's taken nearly 3 years, but I think I have the answer at last... To complete the sequences requires the following numbers: To explain how, I'll take you through my solving process in order... Step 1a: The names The first thing that jumped out at me on seeing the names was that: Step 1b: The number of terms At this point, looking at 'Harry' I noticed ...


6

The missing years from 2021, ..., ..., ..., 2022 may be The list is


5

The next number is: Here is the process to transform a number to find the next one in the sequence : Hence: $1$ becomes $11$ becomes $21$ becomes $22211$ becomes $33221$ becomes $433332211$ becomes $44444444332221$ becomes Research process on paper:


1

You are looking for the 9th Fermat number, $2^{2^8}+1$, which has 78 digits. So the 9th number in your sequence is $78$.


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