[seqfan] Re: A269254 and A034807
djr at nk.ca
Sat Oct 28 00:59:29 CEST 2017
> the sequence to a(10000) showing (currently) 300 unknowns.
> ... I'll be actively working on reducing that number in
> the coming weeks/months:
In case some people don't know.
For those s() sequences with s(0)=1, s(1)=n+1:
if 2k+1 is composite, then s(k) is composite.
On average, it's faster to test 2k+1 and maybe s(k),
than to test s(k).
Don Reble djr at nk.ca
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