Robert, could you make available a list of the primes you found for n <= 18468? Or if you email it to me ( geoff AT hisplace DOT co DOT nz ) I will make it available.
I will keep a list of primes that make the top 5000 list in [url]http://www.geocities.com/g_w_reynolds/Sierpinski5/champs.txt[/url], there is just one entry so far. My results: I found (a while ago) that 32518*5^47330+1 is prime. I am reserving these k: 10918, 12988, 31712. 
Hello all,
I agree with uncwilly that this project should deserve it's own private place... anyone know how to move it? In the meantime: One more down: PFGW Version 20041020.Win_Stable (v1.2 RC1c) [FFT v23.8] Primality testing 42004*5^27992+1 [N1, BrillhartLehmerSelfridge] Running N1 test using base 2 Calling BrillhartLehmerSelfridge with factored part 99.98% 42004*5^27992+1 is prime! (57.0569s+0.0044s) 
Yet another one down
Hi all,
4th prime on here: PFGW Version 20041020.Win_Stable (v1.2 RC1c) [FFT v23.8] Primality testing 44134*5^39614+1 [N1, BrillhartLehmerSelfridge] Running N1 test using base 7 Calling BrillhartLehmerSelfridge with factored part 99.98% 44134*5^39614+1 is prime! (150.2650s+0.0062s) Cheers, Micha 
Hi,
here my newest results: 60124*5^38286+1 is prime! 60394 tested to 50166 ( i keep this reserved) 60722 tested to 49329 ( i keep this reserved) I also keep my other k reserved. Lars 
The primes.txt file in [url]http://www.geocities.com/g_w_reynolds/Sierpinski5/[/url] contains the k,n pairs for all the primes k*5^n+1 found so far. It can be used as input to Proth.exe in file mode, or by adding 'ABC $a*5^$b+1' to the top, as input to pfgw.

Nought
This may come to nought, actually no, it will come to k+1
What am I talking about? n=0 > k*5^0+1= k+1 Therefore any k still remaining where k+1 is prime can be eliminated, unless that is not in the Sierpinski rule book. Looking at my original list, this would eliminate 7528 and maybe others....not got a list of primes to hand What does this group think of this wheeze? Regards Robert Smith 
n=0
Following on, now I am home:
From the original list n=0 eliminates (and a number of these we have found already higher primes or prp for): 7528 15802 33358 43018 51460 81700 82486 90676 102196 105166 123406 123910 143092 152836 159706 Regards Robert Smith 
[QUOTE=robert44444uk]Therefore any k still remaining where k+1 is prime can be eliminated, unless that is not in the Sierpinski rule book.[/QUOTE]
The definitions of Sierpinski number that I have seen take n to be positive, e.g. [url]http://mathworld.wolfram.com/SierpinskisCompositeNumberTheorem.html[/url], so I think we should leave these k in the list. (If they turn out to be harder than the other k then we could reconsider :) 
[QUOTE=geoff]The definitions of Sierpinski number that I have seen take n to be positive, e.g. [url]http://mathworld.wolfram.com/SierpinskisCompositeNumberTheorem.html[/url], so I think we should leave these k in the list. (If they turn out to be harder than the other k then we could reconsider :)[/QUOTE]
Yves Gallot's site also lists n as having to be greater than or equal to one. [url]http://www.prothsearch.net/sierp.html[/url] 
[QUOTE=pcco74]Yves Gallot's site also lists n as having to be greater than or equal to one. [url]http://www.prothsearch.net/sierp.html[/url][/QUOTE]
This is for base 2 only, 5^0 should be considered too. 
Odds and evens
I posted the following message on Yahoo primenumbers to see whether one of the maths bods can give an answer. I am reasonably confident we should allow n=0
[url]http://groups.yahoo.com/group/primenumbers/message/16018[/url] Regards Robert Smith 
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