[seqfan] Re: A104851

N. J. A. Sloane njas at research.att.com
Sun Feb 5 20:53:59 CET 2012


Harvey said:

(start)
A104851 lists "Primes from merging of 10 successive digits
in decimal expansion of e."  It seems obvious that the primes listed
will depend on how many digits of e are generated before looking for
10-digit primes.  I generated 10 million digits of e and could not find
the first term of the above sequence in them.  On the other hand, using
only 10,000 digits of e I found 398 10-digit primes.  Only 10 of those
398 primes appear in the above sequence, out of a total of 18 terms
included in it.
(end)

Me: this kind of sequence only makes sense if we scan from the left, and record
the primes as they appear. (Otherwise every 10-digit prime will be there.)

So I added this comment:

Scan decimal expansion of e from left to right, recording any 10-digit primes seen. - N. J. A. Sloane, Feb 05 2012

I added a similar comment to A104843, where
it is easier to see what is going on.

It looks like the sequence is simply wrong. Harvey, can you correct it
please? You said "using
only 10,000 digits of e I found 398 10-digit primes."
That should be the real beginning of the sequence!

For A104843 I checked the first few terms by hand, and they look correct.

In A104843 there is this comment:

Cf. A104843 - A104862.

I guess all them should be regarded with suspicion.

Neil




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