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 A247700 #7 Oct 02 2014 22:50:54 %S A247700 1,22,122,212,221,333,1333,3133,3313,3331,22333,23233,23323,23332, %T A247700 32233,32323,32332,33223,33232,33322,122333,123233,123323,123332, %U A247700 132233,132323,132332,133223,133232,133322,212333,213233,213323,213332 %N A247700 Numbers which have d digits "d", whenever one of their digits is "d", ordered by largest digit, then by size of the number. %C A247700 This sequence lists the same terms as A108571, but ordered first by the largest digit in the number, then by size. This way, a truncation to the first 1, 5, 80, 14381,... terms is this very same sequence for bases b=2, 3, 4, 5, ... %e A247700 In base 2, the only number with this property is a(1) = 1. %e A247700 In base 3, this property is again satisfied by 1, but also by the 4 additional terms 22, 122, 212 and 221. They are listed "as such" (without conversion from base 3 to base 10) as a(2),...,a(5). %e A247700 In base 4, there are 75 more terms (involving three digits "3"), listed as a(6),...,a(80). %o A247700 (PARI) a=[];for(d=1,3,n=[10^d\9*d]; for(i=1,#a,t=vector(d+#s=digits(a[i]),j,10^j)~\10;forvec(v=vector(d,j,[1,#t]),c=0;n=concat(n,vector(#t,j,if(setsearch(v,j),d,s[c++]))*t),2));a=concat(a,vecsort(n)));a \\ _M. F. Hasler_, Sep 25 2014 %K A247700 nonn,base %O A247700 1,2 %A A247700 _M. F. Hasler_, Sep 22 2014