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 A090420 #10 Jul 13 2013 12:03:10 %S A090420 2,3,5,7,10,13,14,15,17,19,21,22,30,37,41,42,53,54,55,58,62,67,70,73, %T A090420 78,81,85,86,89,90,97,101,103,107,111,115,117,122,131,137,139,141,143, %U A090420 149,150,159,163,165,166,169,170,177,193,197,199,211,214,215,218 %N A090420 Numbers having a unique representation as concatenation of primes in binary. %C A090420 A090418(a(n)) = 1; subsequence of A090421. %H A090420 Reinhard Zumkeller, <a href="/A090420/b090420.txt">Table of n, a(n) for n = 1..10000</a> %o A090420 (Haskell) %o A090420 a090420 n = a090420_list !! (n-1) %o A090420 a090420_list = filter ((== 1) . a090418) [1..] %o A090420 -- _Reinhard Zumkeller_, Aug 07 2012 %Y A090420 Cf. A004676, A007088. %Y A090420 Cf. A090423 (subsequence). %K A090420 nonn,base %O A090420 1,1 %A A090420 _Reinhard Zumkeller_, Nov 30 2003 %E A090420 Based on corrections in A090418, data recomputed by _Reinhard Zumkeller_, Aug 07 2012