[Citrix]

Originally Posted by robert44444uk

Citrix, what is yor covering set for 1307? Obvioulsy there are not many n for which small factors cannot be found but there are 708 n values in the first 100,000 n which have no factors smaller than 50 million.

For example, my NewPgen file reads (for the "Sierpinski":

51763650:P:0:1307:257
2 123
2 387
2 435
2 723
2 891
2 1131
2 1155
2 1443
2 1491
2 1515
2 1803
2 1947
2 1971
2 1995.....

None of these are prime up to n=4731

You are correct. Some error occured on my end. Thanks for pointing it out. But when I tried use Srsieve, it said all the numbers were eliminated. So I assumed it was a Sierpinksi number of this type. Though now when I run Srsieve it says some numbers are left.

I will stick to values under 512 then. I don't think that 2 can be a sierpinki/riesel number for any base. Nor can any of the low k values.

 
101	5000	903	
167	5000	235	
206	5000	614	
218	5000	465	
236	5000	497	
257	5000	187	Citrix
287	5000	260	
305	5000	1049	
365	5000	616	
368	5000	379	
383	10000	76	Citrix
461	5000	535	
467	5000	288

So if someone was to plot the sierpinski numbers (Y axis) and use the count (x axis) does the slope of the curve eventually become almost 0. If yes then it means that low k values are more likely to produce primes than high k values. Does anyone have enough data to plot this. Any thoughts on why low k's like 2, 3 can never be sierpinski numbers to any base...

Thanks!