[seqfan] Re: Sets of composite numbers
Don Reble
djr at nk.ca
Tue Jul 29 07:42:00 CEST 2014
> First, note that these are different: A075067 claims to be looking for
> at least n consecutive, while A189118 is looking for exactly n.
Other way 'round, actually.
I say A075067 is correct. It is a trivial variation of A000230 and
A045881; perhaps it should refer to them.
> In A075067, a(4) through a(6) should all be 115. There are probably
> further errors.
In A189118, that is. The stated definition gives A100964(n+1)+2.
But the A189118 terms are
a(n) = smallest composite (odd) number greater than a(n-1),
such that a(n)+2n is the first prime after a(n).
I guess that's what the Mathematica program produces. (Can someone
confirm that?)
--
Don Reble djr at nk.ca
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