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 A177193 #3 Mar 30 2012 18:52:40 %S A177193 3,7,11,13,17,19,31,43,59,61,71,101,103,139,179,311,313,347,349,421, %T A177193 463,523,569,571,599,601,617,659,823,1019,1021,1031,1061,1093,1153, %U A177193 1319,1321,1429,1619,1667,1697,1721,1787,1789 %N A177193 The twin primes p such that m and k are also twin primes where m*k=semiprime(p). %e A177193 a(1)=3 because 3*3=semiprime(3) and 3=twin prime, a(2)=7 because 3*7=semiprime(7) and 3,7 are twin primes. %Y A177193 Cf. A001097, A001358, A084126, A084127. %K A177193 nonn %O A177193 1,1 %A A177193 _Juri-Stepan Gerasimov_, May 04 2010 %E A177193 Entries checked and sequence extended beyond 139 - _R. J. Mathar_, May 06 2010