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 A103759 #10 Jul 13 2022 17:08:23
%S A103759 1,12,152,1224,11424,204288,1116000,12499488,164831992,1246404096,
%T A103759 11111646000,206331697152,1146405545280,12174560064000,
%U A103759 161484774162432,1323475438225536,11111116476405192,232965361825996800
%N A103759 a(n) = sigma((10^n - 1)/9), where sigma(n) is the sum of positive divisors of n.
%H A103759 Ray Chandler, <a href="/A103759/b103759.txt">Table of n, a(n) for n = 1..322</a>
%F A103759 a(n) = A000203(A002275(n)). - _Michel Marcus_, Sep 08 2015
%t A103759 Table[DivisorSigma[1,FromDigits[PadRight[{},n,1]]],{n,20}] (* _Harvey P. Dale_, Jul 13 2022 *)
%o A103759 (PARI) a(n) = sigma((10^n - 1)/9); \\ _Michel Marcus_, Sep 08 2015
%Y A103759 Cf. A000203, A002275, A070529.
%K A103759 nonn
%O A103759 1,2
%A A103759 Jun Mizuki (suzuki32(AT)sanken.osaka-u.ac.jp), Mar 28 2005