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 A120232 #4 Jul 20 2017 22:51:26
%S A120232 1,3,2,6,8,4,5,12,14,7,17,18,9,21,10,11,26,27,13,30,32,15,35,16,38,39,
%T A120232 41,19,44,20,47,48,22,23,53,24,25,57,59,60,62,28,29,66,68,31,71,72,33,
%U A120232 75,34,78,80,36,37,84,86,87,89,40,92,93,42,43,98,99,45,102,46,105,107
%N A120232 Inverse of A120231.
%C A120232 A permutation of the natural numbers.
%e A120232 A120231, written as a function, is
%e A120232 {(1,1),(2,3),(3,2),(4,6),(5,7),(6,4),(7,10),(8,5)...}.
%e A120232 Reversing each ordered pair and reordering gives
%e A120232 {(1,1),(2,3),(3,2),(4,6),(5,8),(6,4),(7,5),(8,12)...}.
%e A120232 Suppressing first components leaves
%e A120232 1,3,2,6,8,4,5,12,...
%Y A120232 Cf. A073675, A120230, A120231.
%K A120232 nonn
%O A120232 1,2
%A A120232 _Clark Kimberling_, Jun 11 2006