# [seqfan] Re: There are more terms in this sequence?

Harvey P. Dale hpd1 at nyu.edu
Thu Feb 3 21:07:14 CET 2011

```	The fourth term in the sequence is 148480, not 148840.  There are no further terms up to 5 million.
This short Mathematica program will generate the sequence:
Select[Range[5000000],MemberQ[Accumulate[Divisors[#]^2],#]&]
If anyone wants to try to extend the sequence, changing the "Range" to, for example, [5000001,10000000] would check the next 5 million numbers.
Best,
Harvey

-----Original Message-----
From: seqfan-bounces at list.seqfan.eu [mailto:seqfan-bounces at list.seqfan.eu] On Behalf Of Benoît Jubin
Sent: Thursday, February 03, 2011 2:46 PM
To: Sequence Fanatics Discussion list
Subject: [seqfan] Re: There are more terms in this sequence?

0 is the sum of (the squares of) its first k divisors for two
different values of k (0 and 1): these are two good reasons to include
it in the sequence !

Benoit

On Thu, Feb 3, 2011 at 11:37 AM, Hans Havermann <pxp at rogers.com> wrote:
> Andrew Weimholt:
>
>> Also, should we start with 0, since 0 is the sum of its first 0 divisors?
>
> I dunno. If a number has no divisors, then there is no sum (empty, not
> zero).
>
> Claudio Meller:
>
>> 1, 130, 1860, 148840, 3039520
>
> a(4) = 148480
>
> _______________________________________________
>
> Seqfan Mailing list - http://list.seqfan.eu/
>

_______________________________________________

Seqfan Mailing list - http://list.seqfan.eu/

______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.