2^1381-1

Open composite · C291

NFS Planning

GNFS Murphy estimate: 2.96e-20
SNFS Murphy score: 6.40e-19
Preferred method: SNFS
SNFS possible: Yes
SNFS degree: 7
SNFS skew: 0.95549

Identifiers

Target expression: 2^1381-1
Target link: FactorDB page
Target ID: 1000000000000001381
Target changed: -
Parent query: Same as target
Parent ID: -
Cofactor token: C291
Imported: Jun 03, 2026, 04:29 PM UTC

Raw pmain126 Factorization

8287.462853283623.20314602484365657521.324347780588879609356756802551.5717943157553181705211179112739301167905781641204356084154399.C291

SNFS Polynomial

Polynomial

Degree: 7
Murphy: 6.40e-19
Skew: 0.95549
Selected: Best

n: 365194502587236480903377438354206427090481667262791825140198619232414310893704315666936664288036197625718451641936475616667925231701784472306709811139769913788096388477581878095316273491569509659227639160046679609660677936897055660255326839759234266438465091128157863876351106902110791776719
# 2^1381-1, difficulty: 415.72, skewness: 1.22
# cost: 3.9323e+23, est. time: 187252502.85 GHz days (not accurate yet!)
# Optimized skew: 0.95549 Murphy: 6.40e-19
skew: 0.95549
c7: 1
c0: -4
Y1: -200867255532373784442745261542645325315275374222849104412672
Y0: 1
type: snfs