[seqfan] Re: A098550.

[M. F. Hasler]

On Sun, Nov 30, 2014 at 10:19 PM, L. Edson Jeffery <lejeffery2 at gmail.com> wrote:
>  but it appears that the sequence S of fixed points of A098550 is
> finite and
>
> S = {1, 2, 3, 4, 12, 50, 86}.
>
> I checked this for all n <= 10^4 using a Mathematica program based on the
> existing code in A098550, but that code, which took several hours to run
> even in its original form, is too slow to be useful for trying to extend S.

Interesting. My (now added) PARI code takes only 16 sec.
(on battery powered laptop)  to scan up to a(10^4)=11649
(replace "show" by a+1==i to print the fixed points).
I'll check now up to 10^5.

Maximilian