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 A133136 #5 Oct 10 2016 16:33:19 %S A133136 1,3,9,18,72,342,927,1656,7812,38691,94095,144135,741771,3234951, %T A133136 9692874,12764034,70984341,361041921,984024783,1044876843,7641622611, %U A133136 30235306401,72887134149,90695018313,184635924282,344906882748 %N A133136 Powers of 3 written backwards and sorted. %C A133136 This is to A000244 as A034906 is to A000079. %t A133136 Sort[IntegerReverse[3^Range[0,30]]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 10 2016 *) %Y A133136 Cf. A000244, A034906. %K A133136 base,easy,nonn %O A133136 1,2 %A A133136 _Jonathan Vos Post_, Sep 21 2007