[seqfan] Re: The anti-primary pretenders

[Tomasz Ordowski]

P.S. Note:

The sequence is unbounded, namely a(n!) > n.

Thomas Ordowski

sob., 8 wrz 2018 o 14:12 Tomasz Ordowski <tomaszordowski at gmail.com>
napisał(a):

> Dear SeqFans!
>
> Let a(n) be the smallest k such that n^k =/= n (mod k), for n > 1.
>
> 4, 4, 8, 6, 4, 4, 6, 10, 4, 4, 8, 8, 4, 4, 9, 6, 4, 4, 6, 8, 4, 4, ...
>
> All terms are composite and a(n) > 4 iff n == {0,1} (mod 4).
>
> The sequence is bounded and maybe periodic, as I think.
>
> THE PROBLEM: Find all distinct terms of the sequence.
>
> Cf. the primary pretenders: https://oeis.org/A000790
> and range of A000790: https://oeis.org/A108574
>
> Best regards,
>
> Thomas
> ________
> The symbol =/= means "not congruent to".
>
>