[seqfan] Re: 3-sequences relations using Robert Gerbicz's seeker.c

Georgi Guninski guninski at guninski.com
Tue Aug 24 11:42:21 CEST 2010

```On Mon, Aug 23, 2010 at 10:01:29PM -0400, Charles Greathouse wrote:
> That does sound interesting.  But I think it's infeasible for other
> reasons: the human time needed to sift through the resulting
> sequences.
>
> If (extrapolating) there are a million 3-sequence relationships
> between 200,000 sequences, then we'd expect to the order of a hundred
> million 4-sequence relationships between 200,000 sequences.
>
> In fact, even just the 3-sequence relations seem hard to analyze. If
> there are 500 active SeqFans members (surely an overestimate) then
> each would need to check 2000 sequence relations.  Perhaps half would
> be trivial and anther quarter could be dismissed without much work,
> but that's still 500 difficult relations per person.  50 I could
> imagine; 500 would be too many to ask.  50,000 seems entirely more
> than a person could reasonably check.
>
> Charles Greathouse
> Analyst/Programmer
> Case Western Reserve University
>

Charles, i agree with you.

the post was just a computational experiment, i don't claim it makes any sense or is interesting/worth.

some marginal benefits of the test may be:

1. the experiment was just a toy experiment based on too little number of terms. if instead of 30 terms 100 terms were used the # of relations would be considerably smaller imo. try searching for the integers 1 .. 30 and 1 .. 45 in oeis. (126 vs 67). btw, the choice of just 30 terms may be a big mistake of mine.

to play devil's advocate, the oeis may genuinely contain an enormous number of inter-relations that is infeasible for the humans on seqfan, so what ;)

2. i suppose most people are not interested in *all* sequences, they are *particularly* interested in a small subset of them. so if someone is doing a web search for a sequence or a pair of sequences he may find the list of potential relations and ideally find a nontrivial relation by examining them (that's the main reason i posted a large list. it happened to me when doing web search ironically to end up on my site - the search results were < 10)

3. a new computer program may prune the large number of relations e.g. by verifying them to the max available terms or deleting trivially related (by definition) sequences.

```