[seqfan] Re: A174397 and primes with negative value.

[Klaus Brockhaus]

Maximilian Hasler schrieb:
> As to
>
> %N A050267 Primes of the form 47*n^2-1701*n+10181.
>
> and similar sequences, the terms are not correct since according to
> the definition, this is a list of numbers with some property, and they
> must be listed in increasing size.
>
> In the concrete case at hand, the sequence should read :
>
> A050267 =
> -5209, -5171, -5153, -5039, -5003, -4813, -4759, -4493, -4421, -4079,
> -3989, -3571, -3463, -2969, -2843, -2273, -2129, -1483, -1321, -599,
> -419, 379, 577, 1451, 1667, 2617, 2851, 3877, 4129, 5231, 5501, 6679,
> 6967, 8221, 8527, ...
>
> then decide whether / why "n" should take only nonnegative values.
>
>   
To keep the order of the terms I suggest to clarify the definition:

%N A050267 Primes or negative values of primes in sequence b(n) = 
47*n^2-1701*n+10181, n >= 0.
%C A050267 Terms are listed in the order of appearance in sequence b.

The comment is not really necessary, but may help to explain why the 
terms are not sorted in ascending order.

Klaus