248 473 Exponent Status

PrimeNet Exponent Status

M_n

Status

Details

Composite: proven not-prime with Lucas-Lehmer test

No factors below 2⁶⁷

TF target 2⁴⁴

TF below 2^103 is very unlikely to find new factors due to ECM effort.

P-1

B1 =	263000000
B2 =	2865440107530

ECM

Estimated T-Level: 32.6 ⓘ

Status	Date	User	Residue	Shift
Verified		David Slowinski	69D9	0
Verified		Unknown	69D9	0
Verified		Ken Kiefer	903C70EAC47CE9D9	0
Verified		Brian J. Beesley	903C70EAC47CE9D9	0
Verified		Eivind Triel	903C70EAC47CE9D9	179403
Verified	2016-06-01	MadPoo	903C70EAC47CE9D9	89105

History

Date	User	Type	Result
2025-04-18	tim s	NF	no factor from 2^66 to 2^67
2023-02-11	masser	NF-PP1	Start=6/5, B1=30000000, B2=990000000
2023-02-05	masser	NF-PP1	Start=2/7, B1=30000000, B2=990000000
2023-02-05	masser	NF-PP1	Start=72/47, B1=30000000, B2=960000000
2022-05-29	Sid & Andy	NF-PM1	B1=263000000, B2=2865440107530
2022-03-07	LordJulius	NF	no factor from 2^54 to 2^55
2021-12-05	Seth_Tr	NF-PM1	B1=120000000, B2=57783635910
2021-12-05	Seth_Tr	NF-PM1	B1=120000000
2019-12-31	Gordon Spence	NF	no factor from 2^65 to 2^66
2018-03-12	Gordon Spence	NF	no factor from 2^64 to 2^65
2016-06-01	MadPoo	C-LL	903C70EAC47CE9D9
2016-05-13	Numberwang	NF-PM1	B1=2778, B2=69450
2016-02-23	Mark Rose	NF	no factor from 2^57 to 2^58
2016-01-26	Gordon Spence	NF	no factor from 2^63 to 2^64
2016-01-26	Gordon Spence	NF	no factor from 2^62 to 2^63
2015-08-09	snme2pm1	NF	no factor from 2^61 to 2^62
2014-12-24	Denial140	NF-PM1	B1=10000000, B2=250000000, E=12
2013-10-13	David Campeau	NF-PM1	B1=2575000, B2=74675000, E=12
2013-07-13	lycorn	NF	no factor from 2^60 to 2^61
2012-02-26	Joss	NF-PM1	B1=2525928
2011-07-24	Joss	NF-PM1	B1=2020742
2011-02-07	Joss	NF-PM1	B1=2000000
2009-01-26	Sturle Sunde	NF	no factor from 2^59 to 2^60
2009-01-01	Sturle Sunde	NF	no factor from 2^58 to 2^59

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