[seqfan] Re: Is this sequence related to A046901?

[Marc LeBrun]

David, thanks for the clarification!

Then I'll reverse my core recommendation: if it's a different (although related) sequence, then it should have its own entry (with suitable cross links).  

(This is of course assuming it also meets the normal bar of being accurate, well-defined, not silly, etc).

I do still think any lengthy explanations are best in the wiki, whenever possible.

========

I'd like to take this as an opportunity to encourage contributors to not be shy about submitting sequences that are related to other sequences in non-trivial ways (and sometimes even then -- see for example A000371 and A003465).

The OEIS becomes uniquely valuable -- beyond being just another text wiki -- when there are "hits" against queries from users (which, remember, include both people and, increasingly, bots).  

When related sequences are present in the OEIS to match with -- then we may all benefit from the greater "serendipity cross-section".  But when it requires computation to derive them from other sequences... that isn't going to easily happen automatically.

For example some transforms are exquisitely sensitive to apparently "trivial" things like initial terms or shifting the offset (for instance when the mapping from a(n) to f(a(n)) depends on the factorization of n).  So you can never tell when accommodating a small bit of apparent semantic redundancy may pay off hugely by "caching" or surfacing significant subtle interrelationships.

The OEIS isn't just another repository to "publish" novel technical results in condensed form, it's a means to share that knowledge in a uniquely accessible way.  Don't be silly, but don't be shy.


> On Mar 30, 2021, at 11:25 AM, David Seal <david.j.seal at gwynmop.com> wrote:
> 
> I haven't proved that Ali Sada's sequence is literally the same sequence as A046901, but that it is A046901 with extra terms inserted. The extra terms are a 2 and repetitions of the terms of A046901 - the following shows the start of Ali Sada's sequence, with the terms of A046901 unbracketed and the extra terms bracketed:
> 
> 1, (2, 1,)
> 3, 6, (3, 6,)
> 2, 7, (2, 7,)
> 1, 8, (1, 8,)
> 16, 7, (16, 7,)
> ...
> 
> To be clear, I'm not expressing a view on whether Ali Sada's sequence should have an entry in the OEIS - just saying that if it shouldn't, the reason has to be something other than being the same sequence as A046901.
> 
> David
> 
> 
>> On 30/03/2021 17:18 Marc LeBrun <mlb at well.com> wrote:
>> 
>> 
>>> =Ali Sada
>>> should this be a separate sequence or a comment on A046901?
>> 
>> A comment, since David Seal has proved it's literally the same sequence.
>> 
>> Since your description and his proof are a bit lengthy, making them pages on the OEIS wiki and just putting links to them in the entry itself would probably be best.
>> 
>> 
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> 
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