[seqfan] Re: A question concerning perfect numbers
Giovanni Resta
g.resta at iit.cnr.it
Thu Oct 24 15:23:09 CEST 2013
On 10/24/2013 12:13 PM, Vladimir Shevelev wrote:
> My question is: are there non-perfect such numbers?
> Note, that there are respectively "many" numbers n, for which all their proper evil divisors sum to n (we submit sequence A230587).
Up to 10^9 the numbers I found are
28 = 2^2 * 7
496 = 2^4 * 31
8128 = 2^6 * 127
415800 = 2^3 * 3^3 * 5^2 * 7 * 11
2096128 = 2^10 * 23 * 89
33550336 = 2^12 * 8191
so, 415800 and 2096128.
Giovanni
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