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 A109492 #23 Feb 16 2025 08:32:58 %S A109492 1,3,7,11,13,21,33,37,39,77,91,111,143,231,259,273,407,429,481,777, %T A109492 1001,1221,1443,2849,3003,3367,5291,8547,10101,15873,37037,111111 %N A109492 Divisors of 111111. %C A109492 Note that the smaller repunits R3=111, R4=1111, R5=11111 are semiprimes and have only 4 divisors, which is again the case for the next repunit R7=1111111. - _M. F. Hasler_, Oct 13 2011 %H A109492 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Repunit.html">Repunit</a> %H A109492 <a href="/index/Di#divisors">Index entries for sequences related to divisors of numbers</a> %t A109492 Divisors[111111] (* _Paolo Xausa_, Sep 27 2023 *) %o A109492 (PARI) divisors(111111) \\ _Michel Marcus_, Sep 08 2015 %Y A109492 Cf. A070529, A018282, A018766, A027894, A027893, A027892, A027891, A027890, A027889, A027895. [_M. F. Hasler_, Oct 13 2011] %Y A109492 Cf. A199799 (totatives of 111111), A154549 (111111*n). %K A109492 nonn,fini,full,easy %O A109492 1,2 %A A109492 _Philippe Deléham_, Aug 28 2005