S_{,0,2} sequence
koh
zbi74583 at boat.zero.ad.jp
Sat Jan 21 04:22:51 CET 2006
[Deffinition of {k,l}-Aliquot sequence]
Let S_{k,l}(n)=1/l*Sigma(n)-k*n .
b(n)=S_{k,l}(b(n-1))
If b(n)=b(n+m) then it is called "{k,l}-Aliquot cycle" or "{k,l}-Sociable number of order m".
I will give some examples of {k,l}-Aliquot cycle.
This is S_{0,2} .
Yasutoshi
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%I A000001
%S A000001 6, 12, 14, 28, 48, 62, 112, 124, 160, 189, 192, 254
%N A000001 Let S(n)=1/2*Sigma(n) .
Numbers such that S(S(n))=n, 1/2-Sociable number of order 1 or 2.
%C A000001 Almost all terms are of the form that 2^m*M_k .Where M_k means Mersenne prime 2^k-1.
a(9)=2^5*5 and a(10)=3^3*7 are sporadic solutions. S(a(9))=a(10).
%H A000001 <a href="http://mathworld.wolfram.com/SociableNumbers.html">WathWorld</a>
%Y A000001
%K A000001 none
%O A000001 1,1
%A A000001 Yasutsohi Kohmoto zbi74583 at boat.zero.ad,jp
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