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 A010064 #26 Apr 16 2021 12:44:37 %S A010064 1,3,8,13,18,20,25,30,35,37,42,47,52,54,59,64,73,78,83,85,90,95,100, %T A010064 102,107,112,117,119,124,129,138,143,148,150,155,160,165,167,172,177, %U A010064 182,184,189,194,203,208,213,215,220,225,230,232,237,242,247,249,254 %N A010064 Base 4 self or Colombian numbers (not of form k + sum of base 4 digits of k). %D A010064 Steven R. Finch, Mathematical Constants, Cambridge, 2003, Section 2.24, pp. 179-180. %D A010064 József Sándor and Borislav Crstici, Handbook of Number theory II, Kluwer Academic Publishers, 2004, Chapter 4, pp. 384-386. %H A010064 Donovan Johnson, <a href="/A010064/b010064.txt">Table of n, a(n) for n = 1..10000</a> %H A010064 <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a> %t A010064 s[n_] := n + Plus @@ IntegerDigits[n, 4]; m = 250; Complement[Range[m], Array[s, m]] (* _Amiram Eldar_, Nov 28 2020 *) %Y A010064 Cf. A003052, A010061, A010067, A010070, A230631-A230635. %Y A010064 Related base-4 sequences: A053737, A230631, A230632, A010064, A230633, A230634,A230635, A230636, A230637, A230638, A010065 (trajectory of 1) %K A010064 nonn,base %O A010064 1,2 %A A010064 _Leonid Broukhis_