Recent sequence merges

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Message 994 - Posted: 10 May 2017, 17:44:31 UTC

2 of the aliquot sequences we handle have merged with other sequences:

951060 seems to have merged with 398376
and
372402 seems to have merged with 354620

So 2 more sequences are removed from the to do list of the open sequences below 1 million.
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Speedy51

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Message 1005 - Posted: 22 May 2017, 3:45:20 UTC

Can you please explain in layman terms what you mean when you say 2 sequences seem to have merged? Can you also explain how long it takes to complete sequence?
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Message 1006 - Posted: 25 May 2017, 15:30:45 UTC - in response to Message 1005.  

A Aliquot Sequence is a sequence of numbers where the next number is determined by the proper divisors of the previous number.
So all proper divisors of a number is determined (this is what this Boinc project is doing).
Afterwards all those divisors are summed up to get the next number.

So if you start with 10 it has the divisors 5, 2, 1. Next number would be 8.
Divisors of 8 are 4,2,1. Next number would be 7.

In short:
10: 5+2+1=8
8: 4+2+1=7
7: 1=1
1: 0
So this sequence ends.

This you can do with any starting number.

Sometimes it happens that at some points the list of divisors of 2 sequences is identical. So both sequences have the same "next number".
They merged.
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Message 1008 - Posted: 29 May 2017, 4:46:59 UTC - in response to Message 1006.  

Thank you for the explanation
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Message boards : News : Recent sequence merges



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