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 A027901 #27 Jul 08 2025 17:58:11 %S A027901 1,7,11,13,19,77,91,133,143,209,247,1001,1463,1729,2717,19019,52579, %T A027901 368053,578369,683527,999001,4048583,4784689,6993007,7518797,10989011, %U A027901 12987013,52631579,76923077,90909091,142857143,1000000001 %N A027901 Divisors of 10^9 + 1. %C A027901 The prime factorization of 10^9 + 1 = 7 * 11 * 13 * 19 * 52579, so tau(1000000001) = 2^5 = 32. - _Bernard Schott_, Oct 18 2019 %H A027901 <a href="/index/Di#divisors">Index entries for sequences related to divisors of numbers</a> %e A027901 7 * 142857143 = 1000000001. %e A027901 11 * 90909091 = 1000000001. %e A027901 13 * 76923077 = 1000000001. %t A027901 Divisors[10^9 + 1] (* _Alonso del Arte_, Oct 11 2019 *) %o A027901 (PARI) divisors(10^9+1) \\ _Charles R Greathouse IV_, Jun 23 2017 %Y A027901 Cf. A018768, A133029. %K A027901 nonn,fini,full,easy %O A027901 1,2 %A A027901 _N. J. A. Sloane_