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 A204085 #8 Oct 30 2018 10:31:02 %S A204085 1,3,7,9,13,15,25,27,31,33,37,39,49,51,55,57,61,63,73,75,79,81,85,87, %T A204085 153,155,156,157,163,166,177,179,180,181,187,190,193,195,217,219,226, %U A204085 232,273,275,276,277,283,286,297,299,300,301,307,310,313,315,337 %N A204085 Consider integers m such that both m and 2m are decimal pandigital numbers (A050278). The sequence gives indices of m in A050278. %C A204085 The sequence consists of 184320 terms, the last is a(184320) = 1430987 and the largest m = A050278(1430987) = 4938271605 and corresponding 2m = A050278(3265920) = 9876543210 the largest decimal pandigital number. %Y A204085 Cf. A050278, A203987, A204045, A204058. %K A204085 nonn,fini,base %O A204085 1,2 %A A204085 _Zak Seidov_, Jan 10 2012