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 A119643 #8 Jun 13 2016 12:12:44
%S A119643 6,3,7,1,8,4,10,5,9,2,51,52,43,48,49,45,50,47,46,44,97,31,65,15,73,39,
%T A119643 89,57,81,23,98,32,66,16,74,40,90,58,82,24,99,33,67,17,75,41,91,59,83,
%U A119643 25,94,28,62,12,70,36,86,54,78,20,100,34,68,18,76,42,92
%N A119643 Inverse of permutation in A119898.
%C A119643 Unfortunately A119898 has an offset of 1. Really these are inverse permutations on the nonnegative integers. See A119898 1-digit numbers arranged in alphabetical order of English spelling reversed, then the 2-digit numbers so arranged, then the 3-digit numbers, etc.
%F A119643 a(A119898(n)) = n.
%e A119643 a(0) = 6 because A119898(6) = 0.
%e A119643 a(10) = 51 because A119898(51) = 10.
%t A119643 f[a_, b_] := Sort@ Table[{StringReverse[ StringReplace[ IntegerName[h, "Words"], {"\[Hyphen]" -> ""}]], h}, {h, a, b}]; u = Last /@ Join[f[0, 9], f[10, 99]]; a = Range[100] 0; Do[a[[1 + u[[x]]]] = x, {x, 99}]; a (* _Giovanni Resta_, Jun 13 2016 *)
%Y A119643 Cf. A119898.
%K A119643 nonn,word,less
%O A119643 0,1
%A A119643 _Jonathan Vos Post_, Aug 05 2006
%E A119643 Data corrected by _Giovanni Resta_, Jun 13 2016