[seqfan] Re: list of all non-prime coprimes of the full set of primorial numbers

Jamie Morken jmorken at shaw.ca
Fri Apr 21 05:47:19 CEST 2017

Hi,>The definition is not clear.  Note that  gcd(121,2310)=11, so why is
>121 on the list?
>Or, if 121 is on the list, why not 49?

121 is on the list as gcd(121,210)=1, the sequence includes all coprimes as long as they are coprime
to at least one primorial x.  49 isn't on the list as I only included coprimes of primorials if they 
are smaller than the primorial.  49 isn't coprime to any primorial greater than Pn(3) = 30 so it isn't on
the list.>Also, what is Pn? What is the difference between Pn(210) and 210 ? >Did you mean to say >Pn(4) = 210 rather than Pn(210)? >Best regards >NeilYes thanks I meant to say Pn(4) = 210, where 210 is the fifth primorial, and Pn(0) = 1
>Best regards

reply to Franklin:
>The full set of primorials is infinite, and only 1 is coprime to all of them. This is just the numbers coprime to 210, which is rather arbitrary.

The values that are coprime to 210 also contains 253 which isn't in the list (see updated definition of coprimes smaller than Pn only included in the sequence).

Should I resubmit the sequence if the definition is correct now?  Thanks.


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