The recorded dates when this was observed – 1639 – 1761-1769-1874-1882-2004-2012- and predicted in 2014

Why the decrease from 8 years to 2? ]]>

If I remember correctly, you can find an interesting summary in Ilan Vardi’s book “Computer Recreations with Mathematics” ]]>

1, 4, 9, 61, 52, 63, 94, 46, 18, …

Hint: Your intuition on the first 3 numbers is partially correct.

]]>Related exercise: show that the largest digit that occurs in the sequence is “3”.

Another twist on the original sequence:

0, 10, 1110, 3110, 132110, 1113122110, etc….

[I like starting this pattern with 0, as that strikes me as being consistent with the overall process.]

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