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A001270 Table of prime factors of 10^n - 1 (with multiplicity). 8
3, 3, 3, 3, 11, 3, 3, 3, 37, 3, 3, 11, 101, 3, 3, 41, 271, 3, 3, 3, 7, 11, 13, 37, 3, 3, 239, 4649, 3, 3, 11, 73, 101, 137, 3, 3, 3, 3, 37, 333667, 3, 3, 11, 41, 271, 9091, 3, 3, 21649, 513239, 3, 3, 3, 7, 11, 13, 37, 101, 9901, 3, 3, 53, 79, 265371653 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The length of the n-th row is A057951(n).

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

Ray Chandler, Rows n = 1..322, flattened (from Kamada link)

J. Brillhart et al., Factorizations of b^n +- 1, Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 3rd edition, 2002.

Makoto Kamada, Factorizations of 11...11 (Repunit).

S. S. Wagstaff, Jr., The Cunningham Project

MATHEMATICA

Table[f = FactorInteger[10^n - 1]; Flatten[Table[Table[i[[1]], {i[[2]]}], {i, f}]], {n, 13}] (* T. D. Noe, Jun 27 2012 *)

CROSSREFS

Cf. A002283.

Sequence in context: A087576 A201700 A087575 * A029630 A170858 A024725

Adjacent sequences:  A001267 A001268 A001269 * A001271 A001272 A001273

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane

EXTENSIONS

Erroneous b-file replaced by Ray Chandler, Apr 26 2017

STATUS

approved

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Last modified February 20 07:52 EST 2020. Contains 332069 sequences. (Running on oeis4.)