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 A097583 #15 Apr 23 2022 14:56:33
%S A097583 1,14,173,2322,30071,361100,4553207,57060516,726746425,133767016076,
%T A097583 21756176604103,3404420603635070,536705213574536755,
%U A097583 104420417226264430242,15305164771273206577527
%N A097583 Octal representation of the concatenation of the first n decimal numbers with the most significant digits first.
%H A097583 Seiichi Manyama, <a href="/A097583/b097583.txt">Table of n, a(n) for n = 1..337</a>
%F A097583 a(n) = A007094(A007908(n)). - _Seiichi Manyama_, Apr 23 2022
%e A097583 1234 decimal is 2322 octal the 4th entry in the table.
%t A097583 Table[FromDigits[IntegerDigits[FromDigits[Flatten[IntegerDigits/@ Range[ n]]],8]],{n,20}] (* _Harvey P. Dale_, Aug 11 2021 *)
%Y A097583 Cf. A007908, A050926, A097580, A097582.
%Y A097583 Cf. A007094.
%K A097583 base,nonn
%O A097583 1,2
%A A097583 _Cino Hilliard_, Aug 29 2004