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 A004228 #15 Oct 25 2023 07:41:41 %S A004228 0,3010,4771,6020,6989,7781,8450,9030,9542,10000,10413,10791,11139, %T A004228 11461,11760,12041,12304,12552,12787,13010,13222,13424,13617,13802, %U A004228 13979,14149,14313,14471,14623 %N A004228 a(n) = 10000*log_10(n) rounded down. %t A004228 Floor[10^4 Log[10,Range[30]]] (* _Harvey P. Dale_, Feb 07 2015 *) %Y A004228 Cf. A004229, A004230. %Y A004228 Cf. A004216, A004219, A004222, A004225. %K A004228 nonn %O A004228 1,2 %A A004228 _N. J. A. Sloane_