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 A080802 Smaller of the two factors of the n-th semiprime number of the form m!-1. 2
 7, 23, 29, 1733, 3041, 124769, 51871, 625793187653, 20431, 29, 10398560889846739639, 155166770881, 9190813196017748117, 340777, 3282689, 61, 895269581, 21289796287569735866708594882309656982337071, 14380211646881467415803462581621417951534002839, 884057, 139, 7533609175373352257, 1712114014849097863989021395568379341467597467171639484099 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS To continue the sequence the factorizations of 151!-1 and 154!-1 are required, which are composite numbers with 265 and 272 digits, respectively. The next term would then be 37272934189201737869016720929 (factor of 157!-1). 151!-1 has been factored into P58*P208. - Hugo Pfoertner, Jul 18 2019 LINKS Dario Alejandro Alpern, Factorization using the Elliptic Curve Method Paul Leyland, Factor table Hisanori Mishima, Factors of n! - 1 FORMULA Numbers p such that p*q=A078781(n)!-1, p, q prime, p

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Last modified October 20 15:15 EDT 2019. Contains 328267 sequences. (Running on oeis4.)