When product sigma(k)/d(k) = integer
Leroy Quet
qq-quet at mindspring.com
Sun Jun 26 22:24:49 CEST 2005
>Leroy Quet wrote:
>> For which n's is
>>
>> product{k=1 to n} sigma(k)/d(k)
>>
>> an integer?
>>
>> (sigma(k) is sum{j|k} j, and d(k) = sum{j|k} 1.)
>>
>> Is this sequence in the EIS?
>
>At a quick glance, the only positive integers *not* in the sequence
>appear to be 2 and 10. Every other integer up to 5000 is in the
>sequence.
Hmmmm....the question occurs to me and to most probably to others on the
list, is the sequence of n's where the product to n is not an integer a
finite sequence?
And if so, what is the top n? Is it 10?
thanks,
Leroy Quet
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