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next Prime method from sci.math post


I read a post several days ago that said you could find a prime between
n and n+Log[n]^2.
( there also seems to be a NextPrime[] function in Mathematica that I 
wasn't aware of)
I tried the average of the two and it works very well
 such that there are only a few primes that don't fit that pattern:

(* Primes that aren't at the average of n and n+Log[n]^2 *)
Clear[f]
digits=10000
f[n_]:=Floor[n+Log[n]^2/2]
a=Delete[Union[Table[If[PrimeQ[f[n]]==True,f[n],0],{n,1,digits}]],1];
b=Table[Prime[n],{n,1,Dimensions[a][[1]]}];
Complement[b,a]
{5,37,97,421,673,2659,3407,3847,7703}
Respectfully, Roger L. Bagula

tftn at earthlink.net, 11759Waterhill Road, Lakeside,Ca 92040-2905,tel: 619-5610814 :
alternative email: rlbtftn at netscape.net
URL :  http://home.earthlink.net/~tftn


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