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 2021-06-02, 07:00 #1 sweety439     Nov 2016 47·61 Posts Might miss small sociable number OEIS sequence https://oeis.org/A003416 may not be complete to 1799281330, also the site http://djm.cc/sociable.txt, since it is not even known whether 56440 is a member of sociable number, however, if so, the length of the cycle of 56440 must be >5000 Reference: http://factordb.com/sequences.php?se...20&fr=0&to=100 Note that the Aliquot sequence of 1578 merges with that of 56440 Last fiddled with by sweety439 on 2021-06-02 at 07:01
 2021-06-02, 07:18 #2 LaurV Romulan Interpreter     Jun 2011 Thailand 13·733 Posts I believe 276 is a "social distance" number. That means it is a social number, but it will be a long distance till somebody will find out that the sequence 276 ends in 276. (edit: or we can have a cycle that includes all Lehmer's Five, why not? hehe). So, yeah, you are right, those OEIS sequences are not complete... (Oh Dear Mighty God, he is back...) Last fiddled with by LaurV on 2021-06-02 at 07:26
2021-06-02, 07:40   #3
sweety439

Nov 2016

1011001100112 Posts

Quote:
 Originally Posted by LaurV I believe 276 is a "social distance" number. That means it is a social number, but it will be a long distance till somebody will find out that the sequence 276 ends in 276. (edit: or we can have a cycle that includes all Lehmer's Five, why not? hehe). So, yeah, you are right, those OEIS sequences are not complete... (Oh Dear Mighty God, he is back...)
276 is not possible in a sociable cycle, since it is an untouchable number (https://oeis.org/A005114)

Last fiddled with by sweety439 on 2021-06-02 at 07:42

 2021-06-02, 07:59 #4 LaurV Romulan Interpreter     Jun 2011 Thailand 100101001110012 Posts Doh, you got me there! Last fiddled with by LaurV on 2021-06-02 at 07:59
 2021-06-03, 17:20 #5 Stargate38     "Daniel Jackson" May 2011 14285714285714285714 2×331 Posts Maybe a later term will be the cycle's start. We don't know if that'll happen yet, but the later terms aren't untouchable. Other sequences (i.e. 10000018198 and 31657014970784) merge with 276. Last fiddled with by Stargate38 on 2021-06-03 at 17:21
 2021-06-08, 16:14 #6 sweety439     Nov 2016 47×61 Posts See related thread https://mersenneforum.org/showthread.php?t=22701

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