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 A175510 #3 Mar 30 2012 18:52:39 %S A175510 -1,1,3,7,15,25,33,43,45,55,63,61,69,55,81,37,63,67,93,73,141,133,159, %T A175510 163,207,217,231,247,261,355,363,349,375,343,477,469,483,439,465,457, %U A175510 531,439,447,439,453,505,525,439,441,469,477,469 %N A175510 (2*n)-th twin prime minus 2*(n-th twin prime). %F A175510 a(n)=A001097(2n)-2*A001097(n). %e A175510 a(1)=-1 because A001097(2*1)-2*A001097(1)=5-2*3=-1. %Y A175510 Cf. A066066. %K A175510 sign %O A175510 1,3 %A A175510 _Juri-Stepan Gerasimov_, Jun 02 2010