26-digit factor of (M+2)82589933 by ECM by mprime287-OSX

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bearnol

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May 25, 2020, 6:48:28 AM5/25/20
to Mersenneplustwo

[Mon May 25 06:42:23 2020]

ECM found a factor in curve #27, stage #2

Sigma=2912612216072525, B1=250000, B2=25000000.

2^82589933+1 has a factor: 17973642059656480077259129 (ECM curve 27, B1=250000, B2=25000000)


? (2^82589933+1)%17973642059656480077259129

%1 = 0


Jamess-iMac:~ james$ time (echo '17973642059656480077259129' | bc | tr -d '\\\n';echo) | documents/math/gmp-ecpp/atkin251 -q

random seed = 1591114572

error_shift = 1000

precision = 10000

Bmax = 2000

Dmax = 20

N[0] = 17973642059656480077259129

a = 0

b = 11749563742650692115849481

m = 17973642059663872473380901

q = 47013473708893

P = (3929325902, 11080135350800411226844225)

P1 = (0, 1)

P2 = (9977524242683966744807853, 11501345732412404543760482)

Bmax = 2000

Dmax = 20

N[1] = 47013473708893

a = 0

b = 46131236257413

m = 47013460724991

q = 15671153574997

P = (4104368483, 40069241088063)

P1 = (0, 1)

P2 = (16602596174452, 1968292754651)

Bmax = 2000

Dmax = 20

N[2] = 15671153574997

a = 0

b = 10214535812815

m = 15671161340793

q = 248748592711

P = (485075308, 6635568045708)

P1 = (0, 1)

P2 = (12454839960377, 3103851943846)

Bmax = 2000

Dmax = 20

N[3] = 248748592711

a = 0

b = 178189128735

m = 248749580793

q = 1692174019

P = (650158144, 88430893777)

P1 = (0, 1)

P2 = (56587880963, 215354843270)

Bmax = 2000

Dmax = 20

N[4] = 1692174019

a = 0

b = 407224654

m = 1692233292

q = 898213

P = (662673500, 1292498287)

P1 = (0, 1)

P2 = (1351363812, 64130366)

proven prime


real 0m6.412s

user 0m4.079s

sys 0m0.036s


Jamess-iMac:~ james$ time (echo '17973642059656480077259128' | bc | tr -d '\\\n';echo) | documents/math/superfac/superfac13 -e

random seed = 1590555434

base = 351386229831369

number to be tested:

2

2

2

3

743

B=1000, curve#1, a=975427523169956                    

82589933

B=1000, curve#1, a=96456237293623                    

12377

986037719


real 0m0.139s

user 0m0.052s

sys 0m0.014s


Jamess-iMac:~ james$ time (echo '17973642059656480077259130' | bc | tr -d '\\\n';echo) | documents/math/superfac/superfac13 -e

random seed = 1590420970

base = 1063110314487780

number to be tested:

2

5

37

B=1000, curve#1, a=254121976639030                    

338161

143651724983201909


real 0m0.037s

user 0m0.028s

sys 0m0.013s


? FindGroupOrder(p,s)=

{

    K = Mod(1,p);

    v = K*(4*s);

    u = K*(s^2-5);

    x = u^3;

    b = 4*x*v;

    a = (v-u)^3*(3*u+v);

    A = a/b-2;

    x = x/v^3;

    b = x^3 + A*x^2 + x;

    E = ellinit([0,b*A,0,b^2,0],K);

    factor(ellcard(E))

}

%2 = (p,s)->K=Mod(1,p);v=K*(4*s);u=K*(s^2-5);x=u^3;b=4*x*v;a=(v-u)^3*(3*u+v);A=a/b-2;x=x/v^3;b=x^3+A*x^2+x;E=ellinit([0,b*A,0,b^2,0],K);factor(ellcard(E))

? FindGroupOrder(17973642059656480077259129,2912612216072525)

%3 = 

[      2 2]


[      3 4]


[     13 1]


[     19 1]


[    491 1]


[    859 1]


[   8539 1]


[   9103 1]


[6850589 1]


bearnol

unread,
Jul 11, 2020, 2:23:49 PM7/11/20
to Mersenneplustwo

[Sat Jul 11 19:21:00 2020]

2^82589933+1/3/17973642059656480077259129 is not prime.  RES64: 460157BF4252EB66. We10: C404A363,00000000


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