[seqfan] Re: Questions on A230492

[Donovan Johnson]

Michel,

The 6th perfect number is a term in A230492. I checked all 2^34-1 positive sums. Each one is >= the previous sum. 131072 times they are equal.

I am checking the 7th perfect number right now.

Regards,
Donovan






On Thursday, December 19, 2013 12:33 PM, "michel.marcus at free.fr" <michel.marcus at free.fr> wrote:
 

Hi SeqFans, 
  
I have recently extended A230492 to 250 terms. Unless mistaken, it still verify the property that even terms are perfect. 
I have also checked that the 5 first perfect numbers (A000396) belong to this sequence (the 6th one is taking some time). 
  
Is it possible to prove that perfect numbers are in A230492, but no other even numbers ? 
And what could be said about the odd terms ? 
  
I have searched the OEIS and found only 2 other sequences with the same property: 
A034897   Hyperperfect numbers. 
A225417   Composite numbers which contain their sum of aliquot parts as a substring.  
Are there others ? 
  
Thank you for your help. 
Michel 


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