# [seqfan] Re: UnitaryPhi

rgwv at rgwv.com rgwv at rgwv.com
Sun Sep 2 06:55:30 CEST 2018

```or 0 if unknnown.
{2, 3, 4, 5, 144, 7, 8, 9, 400, 11, 64281600, 13, 84672, 129600, 16, 17, 518400, 19, 0, 254016, 0, 23, 0, 25, 0, 27, 3136, 29, 0, 31, 32, 0, 0, 0, 5184, 37, 0, 0, 0, 41, 0, 43, 0, 0, 0, 47, 0, 49, 0, 5992704, 0, 53, 0, 0, 0, 0, 0, 59, 0, 61, 0, 0, 64, 0, 0, 67, 0, 0, 0, 71, 0, 73, 0, 0, 0, 0, 0, 79, 0, 81, 0, 83, 0, 0, 0, 0, 0, 89, 0, 0, 0, 0, 0, 0, 0, 97, 0, 0, 0}
a(pp) = pp iff pp is a prime power (A000961) > 1.

-----Original Message-----
From: SeqFan <seqfan-bounces at list.seqfan.eu> On Behalf Of Ami Eldar
Sent: Friday, 31 August, 2018 10:41 AM
To: Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
Subject: [seqfan] Re: UnitaryPhi

a(12)=64281600 (and I didn't do it mentally...)

On Fri, Aug 31, 2018 at 7:08 AM, <zbi74583_boat at yahoo.co.jp> wrote:

>     Hi Seqfans    See A145680  It is defined as follow
>     The smallest number m such that UnitarySigma(m)=(n+1)/n*m
>     I replaced UniitarySigma by   UnitaryPhi
>     The smallest number m such that UnitaryPhi(m)=(n-1)/n*m
>     a(n) : 2, 3, 4, 5, 144, 7, 8, 9, 400, 11, -, 13, 2^12*3^4*5^2*7^2,
> 2^9*3^4*5^2*73, 16, 17, 2^8*3^4*5^2, 19, -
>     I computed some term   mentally  Could anyone confirm them and compute
> more terms?  Still a(12) is unknown
>
>
>     Yasutoshi
>
> --
> Seqfan Mailing list - http://list.seqfan.eu/
>

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