[seqfan] Re: A180364

[Charles Greathouse]

Yes, let's recycle it and add a comment to the 3n+1 sequence.

Charles Greathouse
Analyst/Programmer
Case Western Reserve University


On Mon, Aug 25, 2014 at 3:42 PM, <israel at math.ubc.ca> wrote:

> Speaking of Fabeny: R. J. Mathar commented Dec 10 2010 on his A180364:
> "Will this diverge from A016777 at some point?".  It's easy to see that
> the answer is no. A180364(n) is    floor(A179896(n) / A018252(n)) where
> A179896(n) mod A018252(n) <> 0
> But A179896(n)/A018252(n) is 3/2*(A018252(n)-1), and this is a non-integer
> precisely when A018252(n) is even.  Since the n'th even nonprime is 2*n+2,
> A180364(n) = floor(3/2*(2*n+1)) = 3*n + 1 = A016777(n).
>
> Shall we recycle A180364?
>
> Cheers,
> Robert
>
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