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 A004426 #25 Oct 26 2023 00:20:03
%S A004426 0,1,2,3,4,5,6,7,8,9,0,1,1,2,2,3,3,4,4,5,1,1,2,2,3,3,4,4,5,5,1,2,2,3,
%T A004426 3,4,4,5,5,6,2,2,3,3,4,4,5,5,6,6,2,3,3,4,4,5,5,6,6,7,3,3,4,4,5,5,6,6,
%U A004426 7,7,3,4,4,5,5,6,6,7,7,8,4,4,5,5,6,6,7,7,8,8,4,5,5,6,6,7,7,8,8,9,0,0,1,1,1,2,2,2
%N A004426 Arithmetic mean of digits of n (rounded down).
%C A004426 From _Reinhard Zumkeller_, May 27 2010: (Start)
%C A004426 A004427(n) <= a(n);
%C A004426 a(A061383(n)) = A004427(A061383(n));
%C A004426 a(A000040(n)) = A074461(n). (End)
%H A004426 Reinhard Zumkeller, <a href="/A004426/b004426.txt">Table of n, a(n) for n = 0..10000</a>
%H A004426 <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%F A004426 a(n) = floor(A007953(n)/A055642(n)). - _Reinhard Zumkeller_, May 27 2010
%t A004426 Table[Floor[Mean[IntegerDigits[n]]], {n, 0, 99}] (* _Enrique Pérez Herrero_, Sep 28 2013 *)
%o A004426 (Haskell)
%o A004426 a004426 n = (a007953 n) `div` (a055642 n)
%o A004426 -- _Reinhard Zumkeller_, Jun 18 2013
%Y A004426 Cf. A175688.
%K A004426 nonn,base
%O A004426 0,3
%A A004426 _N. J. A. Sloane_