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 A032857 #11 Feb 12 2021 22:05:46
%S A032857 1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,22,23,24,25,26,27,28,29,
%T A032857 33,34,35,36,37,38,39,44,45,46,47,48,49,55,56,57,58,59,66,67,68,69,77,
%U A032857 78,79,88,89,99,110,111,120,121,122,130,131
%N A032857 Numbers whose base-10 representation Sum_{i=0..m} d(i)*10^i, d(m) > 0, has d(m) <= d(m-1) >= d(m-2) <= ...
%C A032857 The second digit must be greater than or equal to the first, the third digit must be less than or equal to the second, etc. - _M. F. Hasler_, Mar 08 2014
%o A032857 (PARI) is_A032857(n)=!for(i=2,#n=digits(n),(n[i]-n[i-1])*(-1)^i<0&&return) \\ _M. F. Hasler_, Mar 08 2014
%K A032857 nonn,base
%O A032857 1,2
%A A032857 _Clark Kimberling_