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 A172097 #6 Mar 30 2012 18:52:04 %S A172097 3,3,7,3,7,11,15,3,7,11,15,19,23,27,31,3,7,11,15,19,23,27,31,35,39,43, %T A172097 47,51,55,59,63,3,7,11,15,19,23,27,31,35,39,43,47,51,55,59,63,67,71, %U A172097 75,79,83,87,91,95,99,103,107,111,115,119,123,127,3 %N A172097 Table T(n,k) read by rows which contains in row n the 2^n terms of A171968 starting at the (n+1)st 3. %C A172097 The positions of the 3's in A171968 are 3, 6, 12, ... = A007283(n), or A181565(n) if A171968 is interpreted with offset 1. %e A172097 The table starts in row n as: %e A172097 3; %e A172097 3,7; %e A172097 3,7,11,15; %e A172097 3,7,11,15,19,23,27,31; %Y A172097 Cf. A006257. %K A172097 nonn,tabf %O A172097 0,1 %A A172097 _Paul Curtz_, Nov 19 2010