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 A118098 #12 Sep 08 2018 17:10:09 %S A118098 3,4,6,9,11,51,90,102,105,110,150,201,300,400,501,600 %N A118098 Numbers that require three strokes when written in Roman numerals (excluding serifs). III IV VI IX XI LI XC CII CV CX CL. %C A118098 Unlike the case in A002963, C is counted as one stroke and D is counted as two strokes here. This sequence is complete up to 3999, though it may contain some more terms such as 5000 depending on the convention used to represent larger numbers. - _Nathaniel Johnston_, May 18 2011 %F A118098 Numbers that require three strokes when written in Roman numerals (excluding serifs). %K A118098 nonn,easy,fini,full,base %O A118098 1,1 %A A118098 Dylan Nicholson (wizofaus(AT)hotmail.com), May 11 2006 %E A118098 a(12)-a(16) from _Nathaniel Johnston_, May 18 2011