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 A060443 Table T(n,k) in which n-th row lists prime factors of 2^n - 1 (n >= 2), without repetition. 9
 0, 1, 3, 7, 3, 5, 31, 3, 7, 127, 3, 5, 17, 7, 73, 3, 11, 31, 23, 89, 3, 5, 7, 13, 8191, 3, 43, 127, 7, 31, 151, 3, 5, 17, 257, 131071, 3, 7, 19, 73, 524287, 3, 5, 11, 31, 41, 7, 127, 337, 3, 23, 89, 683, 47, 178481, 3, 5, 7, 13, 17, 241 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS For n > 1, the length of row n is A046800(n). - T. D. Noe, Aug 06 2007 REFERENCES J. Brillhart et al., Factorizations of b^n +- 1. Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 2nd edition, 1985; and later supplements. LINKS T. D. Noe, Rows n=0..500 of triangle, flattened (derived from Brillhart et al.) Joerg Arndt, Rows n=1..1200 of triangle when repetitions are included (derived from Brillhart et al.) J. Brillhart et al., Factorizations of b^n +- 1, Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 3rd edition, 2002. Jeroen Demeyer, Machine-readable Cunningham Tables [Broken link] S. S. Wagstaff, Jr., The Cunningham Project EXAMPLE From Wolfdieter Lang, Sep 23 2017: (Start) The irregular triangle T(n,k) begins for n >= 2: n\k      1   2    3    4   5 2:       3 3:       7 4:       3   5 5:      31 6:       3   7 7:     127 8:       3   5   17 9:       7  73 10:      3  11   31 11:     23  89 12:      3   5    7   13 13:   8191 14:      3  43  127 15:      7  31  151 16:      3   5   17  257 17: 131071 18:      3   7   19   73 19: 524287 20:      3   5   11   31  41 ... (End) CROSSREFS Cf. A001265, A064078. Sequence in context: A337013 A122583 A001265 * A020810 A248895 A021732 Adjacent sequences:  A060440 A060441 A060442 * A060444 A060445 A060446 KEYWORD nonn,tabf AUTHOR STATUS approved

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Last modified November 25 17:54 EST 2020. Contains 338625 sequences. (Running on oeis4.)