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 A066568 #28 Dec 04 2024 16:21:42
%S A066568 0,0,0,0,0,0,0,0,0,0,9,9,9,9,9,9,9,9,9,9,18,18,18,18,18,18,18,18,18,
%T A066568 18,27,27,27,27,27,27,27,27,27,27,36,36,36,36,36,36,36,36,36,36,45,45,
%U A066568 45,45,45,45,45,45,45,45,54,54,54,54,54,54,54,54,54,54,63,63,63,63,63,63
%N A066568 a(n) = n - sum of digits of n.
%C A066568 The sum of the digits of any term of this sequence (A066568) is divisible by 9. - _Alexandre Wajnberg_, Sep 30 2004
%H A066568 Harry J. Smith, <a href="/A066568/b066568.txt">Table of n, a(n) for n = 0..1000</a>
%H A066568 <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%e A066568 a(23) = 23 - 2 - 3 = 18, a(2345) = 2345 - 2 - 3 - 4 - 5 = 2331.
%t A066568 Table[n-Total[IntegerDigits[n]],{n,0,80}] (* _Harvey P. Dale_, Sep 19 2011 *)
%o A066568 (PARI) a(n) = n - sumdigits(n); \\ _Michel Marcus_, Jan 04 2016
%o A066568 (Magma) [n -(&+Intseq(n)): n in [1..100]]; // _Vincenzo Librandi_, Jan 04 2016
%Y A066568 Cf. A060028. - _Reinhard Zumkeller_, Mar 31 2010
%Y A066568 Cf. A066568.
%K A066568 base,nonn
%O A066568 0,11
%A A066568 _Amarnath Murthy_, Dec 18 2001
%E A066568 More terms from Larry Reeves (larryr(AT)acm.org), Dec 21 2001