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
Links
- P. De Geest, Repunits prime factors
- Makoto Kamada, Factorizations of 11...11 (Repunit)
- Eric Weisstein's World of Mathematics, Repunit
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