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 2020-11-29, 20:52 #1 pepi37     Dec 2011 After milion nines:) 24×89 Posts low nash base 10 sequence On Kamada page the is huge number of low nash base 10 sequences ( plus or minus side) Even with very small sieve depth I can remove many candidates, but I would like to do sieve to at least 1e14. And then I have problem since sr2sieve cannot do such depth on sequence like this 5539879179*10^n+1. So does anyone here have some simpler solution except sieving one by one with srsieve and sr1sieve? Update: for now srsieve2 is also in game (and since it is MT) it is fast solution :) Last fiddled with by pepi37 on 2020-11-29 at 21:31
2020-11-30, 08:23   #2
sweety439

Nov 2016

2,819 Posts

Quote:
 Originally Posted by pepi37 On Kamada page the is huge number of low nash base 10 sequences ( plus or minus side) Even with very small sieve depth I can remove many candidates, but I would like to do sieve to at least 1e14. And then I have problem since sr2sieve cannot do such depth on sequence like this 5539879179*10^n+1. So does anyone here have some simpler solution except sieving one by one with srsieve and sr1sieve? Update: for now srsieve2 is also in game (and since it is MT) it is fast solution :)
This k is too large (>2^32), thus sr2sieve cannot handle, like that sr2sieve cannot handle the sequence (k*b^n+c)/gcd(k+c,b-1) (k>=1, b>=2, c != 0, gcd(k,c) = 1, gcd(b,c) = 1) such that gcd(k+c,b-1) is even (if gcd(k+c,b-1) is odd, then we still can use sr2sieve to sieve the sequence k*b^n+c for the prime not dividing gcd(k+c,b-1) and remove the n such that there is some prime p dividing gcd(k+c,b-1) which also divides (k*b^n+c)/gcd(k+c,b-1))

2020-11-30, 22:40   #3
pepi37

Dec 2011
After milion nines:)

24×89 Posts

Quote:
 Originally Posted by sweety439 This k is too large (>2^32), thus sr2sieve cannot handle, like that sr2sieve cannot handle the sequence (k*b^n+c)/gcd(k+c,b-1) (k>=1, b>=2, c != 0, gcd(k,c) = 1, gcd(b,c) = 1) such that gcd(k+c,b-1) is even (if gcd(k+c,b-1) is odd, then we still can use sr2sieve to sieve the sequence k*b^n+c for the prime not dividing gcd(k+c,b-1) and remove the n such that there is some prime p dividing gcd(k+c,b-1) which also divides (k*b^n+c)/gcd(k+c,b-1))

Sweety439, with all due respect , I didnot ask clarification of my problem ( since I also know sr2sieve doesnot working) I ask any "elegant" solution for my problem.

 2020-12-03, 04:52 #4 Citrix     Jun 2003 1,579 Posts srsieve can handle multiple base 10 sequences at once. eg) srsieve.exe --pfgw --nmin 1 --nmax 10000 --pmin 1 --pmax 10000 --factors "3*10^n+1" "2*10^n-1"
2020-12-03, 08:44   #5
pepi37

Dec 2011
After milion nines:)

24×89 Posts

Quote:
 Originally Posted by Citrix srsieve can handle multiple base 10 sequences at once. eg) srsieve.exe --pfgw --nmin 1 --nmax 10000 --pmin 1 --pmax 10000 --factors "3*10^n+1" "2*10^n-1"
Thanks

At the end srsieve2 was the winner since it can handle multiple bases at time and it is MT.

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