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A001271 Irregular table read by rows: row n lists of factors of 10^n +1. 1
2, 11, 101, 7, 11, 13, 73, 137, 11, 9091, 101, 9901, 11, 909091, 17, 5882353, 7, 11, 13, 19, 52579, 101, 3541, 27961, 11, 11, 23, 4093, 8779, 73, 137, 99990001, 11, 859, 1058313049, 29, 101, 281, 121499449, 7, 11, 13, 211, 241, 2161, 9091, 353, 449, 641, 1409, 69857 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

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

Table of n, a(n) for n=0..50.

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

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

EXAMPLE

Table begins:

2,

11,

101,

7,11,13,

73,137,

11,9091,

101,9901,

11,909091,

17,5882353,

...

CROSSREFS

Sequence in context: A243950 A056732 A157715 * A038371 A236174 A003021

Adjacent sequences:  A001268 A001269 A001270 * A001272 A001273 A001274

KEYWORD

nonn,tabf,changed

AUTHOR

N. J. A. Sloane.. Revised Jul 13 2009.

EXTENSIONS

Term ordering corrected by Sean A. Irvine, Apr 11 2012

STATUS

approved

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Last modified November 24 10:51 EST 2014. Contains 249895 sequences.