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 Showing results 1 to 25 of 1000 Search took 0.28 seconds. Search: Posts Made By: R. Gerbicz
 Forum: Information & Answers 2020-10-26, 00:11 Replies: 12 why is P1 no longer awarded? Views: 408 Posted By R. Gerbicz Not checked, but do you reward also the p-1 work... Not checked, but do you reward also the p-1 work when it is hidden in the prp test during the (new) gpuowl 7 run?
 Forum: Miscellaneous Math 2020-10-22, 11:58 Replies: 6 Primes made mostly of nines Views: 200 Posted By R. Gerbicz Combined Theorem 1 is enough from... Combined Theorem 1 is enough from https://primes.utm.edu/prove/prove3_3.html with F1=1, F2=10^8668.
 Forum: Software 2020-10-18, 22:55 Replies: 22 Sticky: LLR version 3.8.24 released. Views: 2,957 Posted By R. Gerbicz Basically in the algorithm there is "almost" only... Basically in the algorithm there is "almost" only squarings and very few multplications (at the stuff for error computation). For N=(k*b^n+c)/d using a^d as "base" with Fermat's little theorem if...
 Forum: GpuOwl 2020-10-11, 15:16 Replies: 20 GpuOwl PRP-Proof changes Views: 1,485 Posted By R. Gerbicz What processor bug you would detect with my error... What processor bug you would detect with my error check, actually it would not give any "correct or incorrect" answer because in a non-random FFT implementation it would not pass the error check with...
 Forum: Miscellaneous Math 2020-10-10, 15:59 Replies: 18 Prime Numbers Book Views: 748 Posted By R. Gerbicz On page 39: "The Euler Phi Function is useful... On page 39: "The Euler Phi Function is useful since for all a a^(1+φ(n)) ≡ a (mod n)." This is very false, a small counter-example is a=2, n=4.
 Forum: Math 2020-10-09, 20:12 Replies: 8 Why does a prime p divide a Fermat Number? Views: 302 Posted By R. Gerbicz Really not read, in general I know the shortest... Really not read, in general I know the shortest proofs. Another way: If 2^(2^m)==-1 mod d then for n>m taking this to the 2^(n-m)-th power: 2^(2^n)==1 mod d from this F(n)==2 mod d and the rest is...
 Forum: Math 2020-10-09, 08:52 Replies: 8 Why does a prime p divide a Fermat Number? Views: 302 Posted By R. Gerbicz I've learnt in this nice way:... I've learnt in this nice way: F(n)=2+F(0)*F(1)*F(2)*...*F(n-1), so if we have a common divisor d of F(n) and F(m), where m
 Forum: FermatSearch 2020-10-06, 22:39 Replies: 318 Sticky: New Fermat factors Views: 41,006 Posted By R. Gerbicz As I can remember pfgw is doing this (or... As I can remember pfgw is doing this (or something like that, the constant=50 is not that interesting, we'd catch all known factors if n is not small: n>50): let N=k*2^n+1 and r(u)=u^(2^(n-50)) mod...
 Forum: Programming 2020-10-02, 16:23 Replies: 26 Calculator that can factor and find exact roots of polynomials Views: 3,416 Posted By R. Gerbicz OK, more inputs: (3*x^2)/(2*x+1) Your... OK, more inputs: (3*x^2)/(2*x+1) Your polynomial 3x2 Clearly wrong. Following your way it would mean that 3*x^2=(2*x+1)*3*x^2+R(x) and in this case the remainder would be 3rd degree?...
 Forum: Programming 2020-10-01, 20:46 Replies: 26 Calculator that can factor and find exact roots of polynomials Views: 3,416 Posted By R. Gerbicz Thanks. More examples: polynom: x^5 - 1615*x^4... Thanks. More examples: polynom: x^5 - 1615*x^4 + 861790*x^3 - 174419170*x^2 + 14998420705*x - 465948627343 Irreducible polynomial factors The 4 factors are: x − 653 (x − 103)2 x2 − 756⁢x +...
 Forum: Programming 2020-10-01, 15:24 Replies: 26 Calculator that can factor and find exact roots of polynomials Views: 3,416 Posted By R. Gerbicz There is a bug even in the polynom evaluation... There is a bug even in the polynom evaluation part, try for: x*(x+1)-(x+1) it shows: Your polynomial −1 Clearly wrong. 2020-10-01, 14:36 Replies: 8 largest n such that n^2+1 has prime factors within a set Views: 651 Posted By R. Gerbicz Found 47668 positive integers x for that x^2+1 is... Found 47668 positive integers x for that x^2+1 is 757-smooth, downloadable at: https://drive.google.com/file/d/1etrDpTXK1gF6Z7N9-9PIrUijmvLIXRW-/view?usp=sharing An old link giving all 200-smooth...
 Forum: enzocreti 2020-09-30, 14:17 Replies: 2 How to proof that numbers 18, 108, 1008,...will never be divisible by 6^4? Views: 218 Posted By R. Gerbicz For n>3 the a(n)=10^n+8==8 mod 16 hence it... For n>3 the a(n)=10^n+8==8 mod 16 hence it won't be divisible by even 16=2^4 so not by 6^4. And you can check the n<=3 cases easily since 6^4=1296>1008. 2020-09-29, 17:20 Replies: 8 largest n such that n^2+1 has prime factors within a set Views: 651 Posted By R. Gerbicz Don't know why not use this colossal 57 terms(!)... Don't know why not use this colossal 57 terms(!) arctan formula what I've found, its efficiency isn't competing with Chudnovsky, but using a bunch of computers we could get the result quicker in Wall...
 Forum: GpuOwl 2020-09-28, 10:06 Replies: 147 GpuOwl 7.x Views: 4,573 Posted By R. Gerbicz If you want a simple formula, counting everything... If you want a simple formula, counting everything in squaremod: total cost=Time(p,B1,B2)+(1-Prob(p,B1,B2))*(p-B1) and you should minimize this, where Time(p,B1,B2) is the cost of doing this new... 2020-09-21, 15:41 Replies: 8 Quadratic residue counts related to four squares representation counts Views: 696 Posted By R. Gerbicz It is a triviality, once you know the sum of a... It is a triviality, once you know the sum of a geometric serie, could be known for 2400 years. To make things easier split the proof for odd/even n. 2020-09-20, 20:33 Replies: 8 largest n such that n^2+1 has prime factors within a set Views: 651 Posted By R. Gerbicz See also for lots of big arctan formulas:... See also for lots of big arctan formulas: http://www.machination.eclipse.co.uk/FSChecking.html (last update was at 2013) 2020-09-20, 20:17 Replies: 8 largest n such that n^2+1 has prime factors within a set Views: 651 Posted By R. Gerbicz See: http://oeis.org/A185389 (somewhere there... See: http://oeis.org/A185389 (somewhere there could be a longer computed list also). This problem is solvable by https://en.wikipedia.org/wiki/St%C3%B8rmer%27s_theorem using a Pell type equation,... 2020-09-20, 16:58 Replies: 8 Quadratic residue counts related to four squares representation counts Views: 696 Posted By R. Gerbicz It says that there are floor(2^n+10)/6 quadratic... It says that there are floor(2^n+10)/6 quadratic residues mod 2^n. You need 4 squares for x iff x=4^e*(8*k+7) it is pretty old fact. If you want the count for this for x<2^n then you can set...
 Forum: Miscellaneous Math 2020-09-15, 14:50 Replies: 12 giant number is not a prime Views: 503 Posted By R. Gerbicz I've thought that I understand you, but not.... I've thought that I understand you, but not. Learn more Maths, and more English.
 Forum: Miscellaneous Math 2020-09-15, 13:58 Replies: 12 giant number is not a prime Views: 503 Posted By R. Gerbicz Yes, that is true, since if N denotes your number... Yes, that is true, since if N denotes your number then N+2 is divisible by 3 and N-2 is divisible by 107.
 Forum: GpuOwl 2020-09-08, 23:24 Replies: 64 Things that make you go hmm, concerning gpuowl runs Views: 2,766 Posted By R. Gerbicz Hm, but if you use my prp cf method then you can... Hm, but if you use my prp cf method then you can save that annoying large division. So compute just (3^mp mod mp) mod 2^2048 (or 3^(1+mp)... ) just as if we'd know only d=1, and then apply my prp...
 Forum: GpuOwl 2020-09-08, 22:59 Replies: 64 Things that make you go hmm, concerning gpuowl runs Views: 2,766 Posted By R. Gerbicz Exactly, what I don't understand is that why... Exactly, what I don't understand is that why anyone tries to run something that is clearly not supported, and you can check this easily at https://github.com/preda/gpuowl . It means nothing that it...
 Forum: Puzzles 2020-08-30, 15:17 Replies: 20 Does there exist another power of 2, except 65536, that doesn't contain a power of two digit? Views: 1,380 Posted By R. Gerbicz Congrats, and you could easily generalize it:... Congrats, and you could easily generalize it: this time using only 6 and 9 in the last 50 places ? Mod(2,10^50)^5342684466535587793434484498741672 %26 =...
 Forum: Puzzles 2020-08-30, 12:49 Replies: 20 Does there exist another power of 2, except 65536, that doesn't contain a power of two digit? Views: 1,380 Posted By R. Gerbicz Like these challenges, and how would you kill... Like these challenges, and how would you kill this example: power of two ending last 50 digits using only 1-2: ? Mod(2,10^50)^18530118576724016889332506805003089 %36 =...
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