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 A166733 #7 Jul 19 2017 21:33:17 %S A166733 3,7,9,13,27,31,37,39,49,51,57,63,67,73,79,81,91,93,97,99,103,109,117, %T A166733 123,129,151,153,163,171,181,187,193,201,213,217,223,229,231,237,249, %U A166733 259,277,279,283,289,291,297,301,303,307,319,321,327,361,367,373,381 %N A166733 Numbers n with the property that the concatenation of the trivial divisors of n (i.e., 1 and n) is a prime. %C A166733 Essentially the same as A032664. - _R. J. Mathar_, Oct 23 2009 %e A166733 3 -> 13; 7 -> 17; 9 -> 19; 13 -> 113. %Y A166733 Cf. A120712. %K A166733 nonn,base %O A166733 1,1 %A A166733 _Juri-Stepan Gerasimov_, Oct 20 2009 %E A166733 Edited by _Charles R Greathouse IV_, Apr 24 2010