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 A105269 #5 Mar 30 2012 18:40:28 %S A105269 5,2,3,13,23,37,83,233,283,383,887,2383,2887 %N A105269 "Long" prime Roman numerals. Smallest prime whose Roman numeral representation has n characters. %C A105269 Finite because of ambiguity of representation for n > 3999. This is the prime version of the sequence A036746 defined by John H. Conway. %H A105269 Gerard Schildberger, <a href="/A006968/a006968.txt">The numbers from 1 to 3999 expressed as Roman numerals.</a> %F A105269 a(n) = Min(k in A000040) such that A006968(k) = n. %e A105269 5=V, 2=II, 3=III, 13 = XIII, 23 = XXIII, 37 = XXXVIII, 83 = LXXXIII, 233 = CCXXXIII, 283 = CLXXXIII, 383 = CCCLXXXIII, 887 = DCCCLXXXVII, 2383 = MMCCCLXXXIII, 2887 = MMDCCCLXXXVII. %Y A105269 Cf. A007968, A036746. %K A105269 base,easy,fini,nonn %O A105269 1,1 %A A105269 _Jonathan Vos Post_, Apr 16 2005