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 A220111 #9 Jan 15 2013 13:48:49 %S A220111 0,12,104,1026,10238,102354,1023468,10234587,1023457869 %N A220111 Main diagonal of array T(k,n) = n-th number in which the number of distinct base 10 digits is k. %e A220111 T(1,1) = 0, which is first number in which the number of distinct base 10 digits is 1. That row has only one other element, 1. %e A220111 T(2,2) = 12, which is first number not beginning with a zero in which the number of distinct base 10 digits is 2. The row begins: 10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23,.... %e A220111 0,1,2,3,4,5,6,... %e A220111 10,12,13,14,15,16,17,... %e A220111 102,103,104,105,106,107,108,... %e A220111 1023,1024,1025,1026,1027,1028,1029,... %e A220111 10234,10235,10236,10237,10238,10239,10243,... %e A220111 102345,102346,102347,102348,102349,102354,102356,... %e A220111 1023456,1023457,1023458,1023459,1023465,1023467,1023468,... %Y A220111 Cf. A043537, A031969 (case 4), A220076 (case 6), A218019 (case 7). %Y A220111 Cf. A219743 (case 8), A050278 (pandigital numbers). %K A220111 nonn,base,easy,fini,full %O A220111 1,2 %A A220111 _Jonathan Vos Post_, Dec 05 2012