[seqfan] Re: Conflicting versions of "no 4-term AP"

David Wilson davidwwilson at comcast.net
Tue Jan 5 06:32:22 CET 2016


I added some of those very long ago, sorry if they weren't up to snuff.

> -----Original Message-----
> From: SeqFan [mailto:seqfan-bounces at list.seqfan.eu] On Behalf Of Neil
> Sloane
> Sent: Monday, January 04, 2016 3:59 PM
> To: Sequence Fanatics Discussion list
> Subject: [seqfan] Re: Conflicting versions of "no 4-term AP"
> 
> As a follow-up to my earlier message: In the end there were 20 sequences
> that needed work:
> 
> Summary of increasing sequences avoiding arithmetic progressions of
> specified lengths (the second of each pair is obtained by adding 1 to the
> first):
> 3-term AP: A005836 (>=0), A003278 (>0);
> 4-term AP: A005839 (>=0), A005837 (>0);
> 5-term AP: A020654 (>=0), A020655 (>0);
> 6-term AP: A020656 (>=0), A005838 (>0);
> 7-term AP: A020657 (>=0), A020658 (>0);
> 8-term AP: A020659 (>=0), A020660 (>0);
> 9-term AP: A020661 (>=0), A020662 (>0);
> 10-term AP: A020663 (>=0), A020664 (>0).
> 
> These all now have consistent definitions and offsets.
> 
> There were 4 incorrect sequences:
> A240075 and A240555, which have been repaired (thanks to Maximilian, who
> identified the errors in the Mma code), and A240556 and A240557, which
> have been "deaded".
> Thanks to everyone who helped.
> This project is finished.
> 
> 
> 
> 
> Best regards
> Neil
> [cascade elided]





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