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 A061845 #16 May 02 2020 21:37:02
%S A061845 2,11,15,19,21,75,78,99,108,114,120,135,141,147,156,177,180,198,201,
%T A061845 210,216,225,228,694,698,714,722,738,742,894,898,954,970,978,990,1014,
%U A061845 1022,1054,1070,1102,1110,1138,1142,1178,1190,1202,1210,1294,1298,1334
%N A061845 Numbers that have one of every digit in some base.
%C A061845 Also known as pandigital numbers, especially in base 10.
%H A061845 Alois P. Heinz, <a href="/A061845/b061845.txt">Rows n = 2..8, flattened</a>
%e A061845 Base 3 values are 102_3 = 11, 120_3 = 15, 201_3 = 19, 210_3 = 21.
%e A061845 Triangle begins:
%e A061845 2;
%e A061845 11, 15, 19, 21;
%e A061845 75, 78, 99, 108, 114, 120, 135, 141, 147, 156, 177, 180, 198, 201, ...
%e A061845 694, 698, 714, 722, 738, 742, 894, 898, 954, 970, 978, 990, 1014, 1022, ...
%e A061845 ...
%t A061845 dtn[ L_, base_ ] := Fold[ base*#1+#2&, 0, L ] f[ n_ ] := Map[ dtn[ #, n ]&, Select[ Permutations[ Range[ 0, n-1 ] ], First[ # ]>0& ] ] Flatten[ Join[ Table[ f[ i ], {i, 2, 5} ] ] ]
%Y A061845 Column k=1 gives A049363 (for n>1).
%Y A061845 Last elements of rows give A062813.
%Y A061845 Cf. A050278, A134640, A001563 (row lengths).
%K A061845 base,easy,nice,nonn,tabf
%O A061845 2,1
%A A061845 _Erich Friedman_, Jun 23 2001