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 A054617 #16 Apr 17 2021 01:26:04
%S A054617 0,10,110,1020,10120,100040,1001220,10000060,100010240,1000002060,
%T A054617 10000100440,100000000100,1000001022240,10000000000120,
%U A054617 100000010000660,1000000000204080,10000000100020480,100000000000000160,1000000001002002660
%N A054617 a(n) = Sum_{d|n} phi(d)*10^(n/d).
%H A054617 Seiichi Manyama, <a href="/A054617/b054617.txt">Table of n, a(n) for n = 0..1000</a>
%F A054617 Dirichlet convolution of A000010 and A011557. - _R. J. Mathar_, Jan 11 2013
%F A054617 a(n) = Sum_{k=1..n} 10^gcd(n,k). - _Ilya Gutkovskiy_, Apr 16 2021
%Y A054617 Column k=10 of A185651.
%Y A054617 Cf. A054629.
%K A054617 nonn
%O A054617 0,2
%A A054617 _N. J. A. Sloane_, Apr 16 2000