Alternating sequence
Just so you know
An alternating sequence A(n) = (1)^n Is in Online Encyclopedia of Integer Sequences See [OEIS]033999[/OEIS] Good fun 
Edited your message for coherence.
Don't expect it to happen every time. [SPOILER]It's A033999, not A033998.[/SPOILER] 
I think that's the only pure, nontrivial alternating sequence in the OEIS at the moment. There are A062157, A105812, A117154, A165326, and A280560 which alternate after some finite prefix, and of course A000004 which alternates in a trivial sort of way.

Another interesting sequence is
OEIS.org/A250001 It is about “How many ways can circles overlap?” Everyone is different. Also see a Numberphile video in YouTube Called “How many ways can circles overlap?” The sequence has 1, 3, 14, 173 in the beginning Cheers Matt 
[QUOTE=MattcAnderson;570213]Also see a Numberphile video in YouTube
Called “How many ways can circles overlap?”[/QUOTE]Was it too challenging for you to provide us with a link. The forum even has special markup for YT. Using it will provide for an embedded viewer. 
All times are UTC. The time now is 07:00. 
Powered by vBulletin® Version 3.8.11
Copyright ©2000  2021, Jelsoft Enterprises Ltd.