This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A046414 #28 Feb 16 2025 08:32:39 %S A046414 13,31,37,38,67,73,83,97,101,103,113,127,149,163,191,227,241,263,313, %T A046414 331,373,379 %N A046414 Repunit of length a(n) has exactly 3 prime factors (counted with multiplicity). %C A046414 467 <= a(23) <= 857. 857, 1303, 1483, 2267 are terms of this sequence. - _Chai Wah Wu_, Nov 03 2019 %H A046414 P. De Geest, <a href="https://www.worldofnumbers.com/repunits.htm">Repunits prime factors</a> %H A046414 Makoto Kamada, <a href="https://stdkmd.net/nrr/repunit/">Factorizations of 11...11 (Repunit)</a> %H A046414 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Repunit.html">Repunit</a> %e A046414 a(n)=13 so 1111111111111 = 53*79*265371653. %o A046414 (PARI) is(n)=bigomega(10^n\9)==3 \\ _Charles R Greathouse IV_, Mar 11 2014 %Y A046414 Cf. A000042, A001222, A002275, A004022, A046053. %K A046414 nonn,more,base %O A046414 1,1 %A A046414 _Patrick De Geest_, Jul 15 1998 %E A046414 More terms from _Robert Gerbicz_, Nov 22 2010 %E A046414 More terms from _Bo Gyu Jeong_, Jun 12 2012