eulerphi(0)

Max Alekseyev on Thu, 14 Sep 2017 21:46:33 +0200

eulerphi(0)

To: "pari-users@pari.math.u-bordeaux.fr" <pari-users@pari.math.u-bordeaux.fr>
Subject: eulerphi(0)
From: Max Alekseyev <maxale@gmail.com>
Date: Thu, 14 Sep 2017 15:46:24 -0400
Delivery-date: Thu, 14 Sep 2017 21:46:33 +0200
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=FNoujUQo8fR1R0sgPwE4ORdSARgZSSddNtd6d+BXQyo=; b=CdQ3zd/8wc5GJUsNa3BleVamiCefo9Ew5faaNdHgF8jjpcnb63C8jN/zUS0qVFc+UC FELrmjewWsS9RUwPgEp5oS4rbJoESrF3dUkktIlbI2ChaRfdk/OQYI65IiXaiKkHl5Bo CPC0gSqCi+qFqixoow/F7h+6HhPLSre4l2p8pNid6INwXJvWDfOP8023uGix/B/5WvKK nxXWqSZh9ZCRaBguf+k1s3qP85iN/e7AIJwoGG9vmVxCp0dSK2XdzZq51WiTtiRh9OjG aeFxJGIxZ9mIM4C7ZBhdrZh3tiOlg5UIeIedl3vo8iHg34gaG67ZTxsFlc6LWflhsK+j kOog==

Is there any particular reason behind eulerphi(0) = 2 ?

? eulerphi(0)

%1 = 2

I'd rather expect eulerphi(0) to result in an error.

Zero value would also make more sense, since there are no positive integers <=0 (even if we do not care about co-primality).

Regards,

Max

Follow-Ups:
- Re: eulerphi(0)
  - From: John Cremona <john.cremona@gmail.com>
- Re: eulerphi(0)
  - From: Kevin Buzzard <k.buzzard@imperial.ac.uk>
- Re: eulerphi(0)
  - From: Karim Belabas <Karim.Belabas@math.u-bordeaux.fr>