A046417 Repunit of length a(n) has exactly 6 prime factors (counted with multiplicity).

15, 16, 26, 33, 34, 39, 46, 57, 69, 76, 79, 93, 94, 106, 118, 121, 133, 169, 181, 278, 281, 293

Offset

1,1

Links

Table of n, a(n) for n=1..22.

P. De Geest, Repunits prime factors

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

Eric Weisstein's World of Mathematics, Repunit

Crossrefs

Cf. A000042, A001222, A002275, A004022, A004023, A046053.

Sequence in context: A063530 A160661 A342941 * A193566 A079832 A037971

Adjacent sequences: A046414 A046415 A046416 * A046418 A046419 A046420

Keyword

nonn,base,more

Author

Patrick De Geest, Jul 15 1998

Extensions

More terms from Robert Gerbicz, Nov 22 2010

a(20) from Bo Gyu Jeong, Jun 30 2012

a(21)-a(22) from Ray Chandler, Apr 23 2017

Status

approved