"simple" series not in OEIS yet?

[Jonathan Sondow]

sequence would be automatically checked to see if it is a possible 
such as, "Your sequence may already exist in the database. It may 
submit your sequence?".
seqwuence.
sequence(s):".."Do you still wish to submit this as a new sequence?".
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Subject: Avoiding misidentified comments/extensions:  idea
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Date: Wed, 13 Jun 2007 11:16:03 -0500 (CDT)
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Neil & SeqFans,

Is this a good time or a bad time to offer ideas about changes to the web site?

(Maybe it depends on the idea?) :-)

Here's one (I don't remember having suggested it before, but if I have, please 
forgive me):

Along with the various links that are shown at the bottom of a page of search 
results, i.e., "Lookup," "Welcome," "Find Friends," ... "Contribute new seq. 
or comment" ...

Perhaps a "Comment on this sequence" link could be added.  Clicking on it 
would then bring up a form very similar to the one that comes up when a user 
clicks "Contribute new seq. or comment," except that the "Comment on existing 
sequence number" option button would already be selected, and the correct 
sequence number would already be in its text box.  That should at least help 
to avoid some problems in which a typo (e.g., a reversal of two digits) in 
that text box causes confusion.

Similarly, the "Brief description or definition of sequence" textbox could be 
automatically populated with the existing name.

Also, if this sounds good, the box showing the first several terms could be 
already populated with all the actual terms from the database.  This way, if 
someone wanted to extend the sequence or correct it, I think it would cut down 
on typos and cut/paste errors.

The same could be done with any other fields where it would make sense to do 
so.

... Whatcha think?  (Per Leroy Quet's comment re the idea he offered about 
avoiding duplicates ... feel free to ignore this one, too.)  :-)

Thanks for your time,

-- Jon



Peter, you said 

A042965 seems to be the same as A122906 and A074227 and these could
additionally be described in words as nonnegative integers, which are a
difference of squares.

agree for the first 10^14 terms.  so one must be careful.

What exactly can be proved about equlaties between these three

Q for Paul Barry:  you said:

%F A074227 G.f.: (1+x)^2/(1-x-x^3+x^4); a(n)=sum{k=0..floor((n+1)/2), C(n-k, k)(-1)^k*A001045(n-2k+2)}; - Paul Barry (pbarry(AT)wit.ie), Apr 26 2005

and

%F A042965 G.f.: x(1+x)^2/(1-x-x^3+x^4); a(n)=sum{k=0..floor(n/2), binomial(n-k-1, k)A001045(n-2k)}, n>0. - Paul Barry (pbarry(AT)wit..ie), Jan 16 2005

observations only, based on the initial terms?

Neil



The trouble with Leroy's suggestion is this:

Most users of the OEIS don't know what a "proof" is.
For the average user, the fact that two sequences
agree for a while means they really are the same.
The concept of mathematical proof is Sanskrit to
most people.

So asking someone if their sequence is the same
as another sequence won't do any good.

I see this even with regular contributors:  people
without proof.  I don't have time to ask each
time "Do you have a proof or is that merely an observation
based on the available data?"

Neil